JP2977005B2 - Seal structure of plug valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plug valve seal structure used in a chemical plant, a petroleum refining plant and the like.

[0002]

2. Description of the Related Art Conventionally, as a plug valve used in a chemical plant or a petroleum refining plant, for example, there is a plug valve described in Japanese Patent Application Laid-Open No. 64-69881, and the sealing structure of this plug valve is shown in FIG. It is like. In FIG. 2, a guide tube 2 inserted into a regenerator 1 is welded and fixed to the regenerator 1 around the periphery thereof, and a plug is attached to the tip of a hollow stem tube 3 which is inserted into and out of the guide tube 2 so as to be freely retractable. A closing member (not shown) is provided.

[0003] A chamber 4 is arranged outside the mountain flange 1A of the regenerator 1 so as to cover a base end side opening of the hollow stem tube 3. The chamber 4 is provided with a fixing bolt 41 screwed to the mountain flange 1A and a fixing nut 42 screwed to the fixing bolt 41.
A, and a seal packing 43 is interposed between the chamber 4 and the mountain flange 1A. The chamber 4 is provided with a supply port (not shown) for supplying a fluid G such as lifting air. In addition, hollow stem tube 3
A shaft 5 is connected to the base end of the plug, and the hollow stem tube 3 is retracted by pushing and pulling the shaft 5 to open and close the plug closing member.

A sealing member 60 disposed between the guide tube 2 and the hollow stem tube 3 is fitted into a cylindrical holding member 61 welded and fixed to the regenerator 1 and an appropriate portion inside the holding member 61. A guide liner 62, a compressible sealing packing material 63 interposed between the holding member 61 and the hollow stem tube 3,
An annular spacer 64 interposed between the compressible sealing packing material 63 and the guide liner 62, and one end inserted between the holding member 61 and the hollow stem tube 3 abut on the compressive sealing packing material 63. A ground member 65 and a holding member 61 which hold the ground member 65 so as to be able to move back and forth in the axial direction.
, A nut 67 mounted on the distal end side of the bolt 66, and a compression spring washer 68 interposed between the nut 67 and the ground member 65.

The sealing member 60 receives the urging force of the compression spring washer 68 in a state where the bolt 66 is properly tightened, and the gland member 65 presses the compressible sealing packing material 63, and the compressible sealing packing material 63 is pressed. 63 presses against the inner peripheral surface of the holding member 61 and the outer peripheral surface of the hollow stem tube 3 to seal the gap between the holding member 61 and the hollow stem tube 3. The regenerator 1 is provided with a purge gas supply port 1a. The purge gas supply port 1a communicates with the gas filling space 64a formed by the spacer 64 through the guide tube 2 and the ventilation ports 2a, 61a provided in the holding member 61. doing.

[0006]

However, in the above-mentioned conventional structure, the guide liner 62 and the compressible sealing packing material 63 are interposed between the holding member 61 and the hollow stem tube 3. In both the guide liner 62 and the compressible sealing packing material 63, the radial dimension of the hollow stem tube 3 affects the function, and a change in the size of one member affects the function of the other member. For example, when the outer diameter of the guide liner 62 is to be changed, the holding member 61
The result is that the gap between the holding member 61 and the hollow stem tube 3 changes, the surface pressure of the compressible sealing packing material 63 changes, and the sealing property is impaired. is there. Therefore, the dimensions of the guide liner 62 and the compressible sealing gasket 63 cannot be determined independently of each other, and it has been difficult to employ optimal dimensions for each member.

An object of the present invention is to provide a plug valve seal structure in which dimensions of a guide liner and a compressible sealing packing material do not interfere with each other.

[0008]

In order to solve the above problems, a plug valve sealing structure according to the present invention comprises a guide tube inserted into a body, which is welded and fixed to a body wall on an outer peripheral surface.
The hollow stem tube was inserted through the guide tube, a plug closing member was provided at the tip of the hollow stem tube located inside the container, and the chamber was arranged outside the container so as to cover the base end side opening of the hollow stem tube. In the plug valve, an annular holding member is arranged between the guide tube and the hollow stem tube, a guide liner that slides on the hollow stem tube is arranged inside the holding member, and a seal that fits over the hollow stem tube inside the chamber. Along with disposing the retainer, the seal retainer is welded and fixed to the inner surface of the chamber at the outer periphery, and a compressive sealing packing material is interposed between the inner surface of the seal retainer and the outer peripheral surface of the hollow stem tube, thereby forming a hollow. An annular gland member, which is fitted to the stem tube and presses the compressible sealing packing material, is disposed in the chamber between the body wall and the seal holder, and the gland member is hollowed out. A bolt holding the tube so as to be able to move back and forth in the axial direction of the pipe is screwed into the seal holder, and the gland member is pressed toward the compressible sealing packing material between the nut and the gland member mounted on the tip side of the bolt. It has a compression spring washer interposed.

[0009]

According to the above construction, the guide liner is located between the inner peripheral surface of the holding member and the outer peripheral surface of the hollow stem tube, and seals the periphery of the hollow stem tube on the side of the body. It is located between the inner peripheral surface of the seal holder and the outer peripheral surface of the hollow stem tube to seal around the hollow stem tube on the chamber side. Therefore, since there is no structural relationship between the guide liner and the compressible sealing packing material, changing the dimensions of the guide liner only affects the retaining member, and It does not affect the sealing performance of the packing material. Moreover,
In addition to the pressing force of the compression spring washer, the pressure in the chamber between the body wall and the seal holder acts as a force for pressing the gland member against the compressible sealing packing material, so that the compressible sealing packing is formed. The sealing property by the substance is improved.

[0010]

An embodiment of the present invention will be described below with reference to the drawings. Components that perform the same operations as those described with reference to FIG. 2 are denoted by the same reference numerals, and description thereof is omitted.

In FIG. 1, a seal holder 11 is arranged inside a chamber 4 so as to be fitted to the hollow stem tube 3.
The seal holder 11 is welded and fixed to the inner surface of the chamber 4 on the outer periphery. Between the inner surface of the seal holder 11 and the outer surface of the hollow stem tube 3, a compressible sealing packing material 1 is provided.
2, an annular gland member 13 that fits over the hollow stem tube 3 and presses the compressible sealing packing material 12
Are disposed in the chamber 4 between the wall surface of the regenerator 1 and the seal holder 11.

A bolt 14 screwed to the seal holder 11 holds the ground member 13 so as to be able to move back and forth in the axial direction of the hollow stem tube 3. A compression spring washer 16 that presses the ground member 13 toward the compressible sealing packing material 12 is interposed therebetween.

The operation of the above configuration will be described below.
The guide liner 62 is located between the inner peripheral surface of the holding member 61 and the outer peripheral surface of the hollow stem tube 3 and seals the periphery of the hollow stem tube 3 on the regenerator 1 side.
Numeral 2 is located between the inner peripheral surface of the seal holder 11 and the outer peripheral surface of the hollow stem tube 3 to seal around the hollow stem tube 3 on the chamber 4 side.

Therefore, since there is no structural relationship between the guide liner 62 and the compressible sealing gasket material 12, even if the dimensions of the guide liner 62 are changed, the influence only affects the holding member 61. Therefore, the sealing performance of the compressible sealing packing material 12 is not affected at all.

The pressure in the portion A of the chamber 4 is smaller than the pressure in the regenerator 1, and the pressure in the portion B is smaller than the pressure in the portion A of the chamber 4. For this reason, in addition to the pressing force of the compression spring washer 16, the pressure in the chamber 4 between the wall of the regenerator 1 and the seal holder 11 presses the ground member 13 against the compressible sealing packing substance 12. Compressive sealing packing material 12 by acting as a force
Sealability is improved.

[0016]

As described above, according to the present invention, since the guide liner and the compressible sealing packing material do not structurally interfere with each other, the shape and dimensions of the guide liner can be reduced by the sealing of the compressible sealing packing material. Has no effect on performance.
In addition, the pressure in the chamber between the body wall and the seal holder acts as a force for pressing the gland member against the compressible sealing packing material, so that the sealing performance by the compressible sealing packing material is improved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a seal structure of a plug valve according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a conventional plug valve sealing structure.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 regenerator 2 guide tube 3 hollow stem tube 4 chamber 11 seal holder 12 compressible sealing packing material 13 annular gland member 14 bolt 15 nut 16 compression spring washer

──────────────────────────────────────────────────の Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F16K 41/04

Claims (1)

(57) [Claims] 1. A guide tube inserted into a body is welded and fixed to a body wall on an outer peripheral surface, a hollow stem tube is inserted through the guide tube, and a plug is closed at a tip of the hollow stem tube located in the body. In a plug valve in which a member is provided, and a chamber is disposed outside the body so as to cover a proximal opening of the hollow stem tube, an annular holding member is arranged between the guide tube and the hollow stem tube, and the inside of the holding member is A guide liner that is in sliding contact with the hollow stem tube is arranged in the chamber, and a seal holder that fits over the hollow stem tube is arranged in the chamber,
The seal holder is welded and fixed to the inner surface of the chamber at the outer periphery, and a compressive sealing packing material is interposed between the inner surface of the seal holder and the outer peripheral surface of the hollow stem tube, and is externally fitted to the hollow stem tube. An annular gland member for pressing the compressible sealing packing material is disposed in the chamber between the body wall and the seal holding body, and a bolt for holding the gland member so as to be able to move back and forth in the axial direction of the hollow stem tube. A plug valve having a compression spring washer threadedly mounted on a seal holder, and a compression spring washer interposed between a nut mounted on a tip end of the bolt and a gland member for pressing the gland member toward a compressible sealing packing material. Seal structure.