JPS63280971A - Valve device - Google Patents

Abstract

PURPOSE:To prevent rapid increase of leakage even in a damaged seat surface by providing a seat ring on which a valve body is seated on a partition wall of the valve body through an elastic ring in which a portion of the valve body is inserted. CONSTITUTION:A communicating hole 4 of a valve seat 3 is provided on the peripheral edge of upper opening end with a recess 6 to which a fixed ring 7 is fixed by welding or press fit. The inner peripheral edge of a seat ring 8 having a seat surface 8a on which a valve body 5 is seated is connected to the inner peripheral edge of a fixed ring 7 through an elastic ring 9. The elastic ring 9 made of thin metal material is subjected to elastic deformation and radially inward bulged as it is pressed axially. When the valve body 5 advances to a partition wall 1, it is first seated on the seat ring 8 to block the flow of fluid. When the valve body 5 further advances, the elastic ring 9 is compressed and deformed by the press force of valve body 5 to bulge radially inward and seal the fluid.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a valve device used for fluid control in, for example, the petroleum industry and the chemical industry.

[Conventional technology]

This type of valve device is configured such that a valve body is provided so as to be movable forward and backward relative to a valve seat fixed to a partition wall of a valve body, and the flow of fluid is closed by seating this valve body on the valve seat. ing.

[Problem that the invention seeks to solve]

However, in this type of conventional valve device, an extremely narrow flow path is formed between the valve element and the valve seat immediately before the valve element seats on the valve seat. Therefore, the flow velocity is the highest in this closed portion, and the valve body or the seat surface of the valve seat may be damaged by cavitation erosion or ablation.

In addition, if a part is damaged, fluid will leak through the damaged part even in a fully closed state, so the damaged part will not only expand rapidly and the amount of leakage will increase, but will also end up being used in a short period of time. There was a problem that made it impossible.

[Means for solving problems]

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a valve device that does not rapidly increase leakage even if the seat surface is damaged, thereby extending the life of the valve device. In the valve device according to the present invention, the seat ring on which the valve body is seated is elastically deformed so as to bulge in the inner diameter direction, and the seat ring is attached to the partition wall of the valve body via the elastic ring through which a part of the valve body is inserted. It is something that

[Effect]

In the present invention, when the valve body moves forward with respect to the partition wall, the elastic ring is compressively deformed and bulges in the inner diameter direction, so that the elastic ring comes into pressure contact with a part of the valve body and seals the fluid.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view of a main part of a first embodiment of a valve device according to the present invention, and FIG. 2 is a cross-sectional view showing the same in a closed state.

What is indicated by the reference numeral 1 in these figures is a partition wall of the valve body, which defines the inside of the valve body into an upstream passage and a downstream passage. An opening 2 is formed in the partition wall l to communicate the upstream passage and the downstream passage. A valve seat 3 is fixed to the partition wall 1 by being screwed into the threaded groove of the opening 2, and a communication hole 4 is opened in the center thereof. 5 is arranged to move freely forward and backward with respect to the valve seat 3 by a valve shaft (not shown).
It is a valve body having a seat surface 5a on which it is seated.

A concave portion 6 is provided at the periphery of the upper opening end of the communication hole 4 of the valve seat 3, and a fixing ring 7 is fixed therein by welding or press fitting. 8 is a seat surface 8 on which the valve body 5 is seated.
The seat ring 9 having a is a metal ring serving as an elastic ring that connects the inner peripheral edge of the seat ring 8 and the inner peripheral edge of the fixed ring 7 to provide the seat ring 8 on the partition wall 1. In other words, the metal ring 9 is integrally formed with the fixed ring 7 and the seat ring 8.

The metal ring 9 is made of a thin metal material that can be elastically deformed, and has an inner diameter that gradually increases toward the upper and lower ends so that it elastically deforms and bulges in the inner diameter direction as it is pressed in the axial direction. It is cylindrical, or drum-shaped.

A shaft-shaped seal portion 5b that protrudes below the seat surface 5a is integrally provided at the lower part of the valve body 5. The amount of protrusion of this seal portion 5b is set to be approximately the height of the seat ring 8 and the metal ring 9 combined, and its outer diameter is set such that the outer peripheral surface comes into pressure contact with the metal ring 9 when the metal ring 9 is elastic. has been done.

Further, the distal end portion 5c of the valve body 5 is formed so that the diameter becomes gradually smaller toward the distal end.

In the valve device configured in this way, when the valve body 5 is retracted with respect to the partition wall l as shown in FIG.
Between the seat surface 8a of the seat ring 8 and the seat surface 5a of the valve body 5,
Since a gap is formed between the metal ring 9 and the tip 5C, fluid can flow through the communication hole 4. On the other hand, when the valve body 5 moves forward with respect to the partition wall 1, it first seats on the seat ring 8, thereby blocking fluid flow. Then, when the valve body 5 moves further forward, the metal ring 9 is compressed and deformed by the pressing force of the valve body 5 and bulges in the inner diameter direction.As shown in FIG. It comes into pressure contact with the fluid and seals the fluid.

Therefore, since the fluid can be closed at two locations, the closing function can be improved compared to a structure where the fluid is closed at one location. Furthermore, after the valve body 5 is seated on the seat ring 8 to stop the flow of fluid, the metal ring 9 and the seal portion 5b can be brought into pressure contact in this state. Therefore, when the metal ring 9 and the seal portion 5b come into pressure contact with each other, it is possible to suppress the influence of the fluid flow on these members, so that the closure can be ensured. In addition, during slurry service, etc., the valve body 5 may be
Immediately before the seat ring 8 is seated, the flow velocity in this vicinity increases, but the seat surface 8a of the seat ring 8 and the metal ring 9 are far apart, and the flow velocity in the vicinity of the metal ring 9 does not increase that much. Seal part 5b
There will be no wear and tear.

Therefore, even if the seat surface 8a or the seat surface 5a is damaged and leakage occurs between the seat ring 8 and the valve body 5, it can be reliably closed with the metal ring 9, and the leakage will rapidly increase. can be prevented. As a result, the life of the valve device can be extended.

In this way, the present invention elastically deforms the elastic ring to form the valve body 5.
The content of the elastic ring is to seal between the valve body 5 and the partition wall 1 by bringing the elastic ring into pressure contact with the above-mentioned seat ring 8 and fixed ring. The metal ring 9 is not limited to the drum-shaped metal ring 9 integrally formed with the metal ring 7, and various modifications can be made.

3 to 6 are cross-sectional views showing the second to fifth embodiments,
In these figures, members that are the same or equivalent to those shown in FIG. 1 are designated by the same reference numerals, and detailed explanation thereof will be omitted. In the second embodiment shown in FIG. 3, a seat ring 8 is used which has a metal ring 9 on its inner periphery and a fixing metal ring 11 on its outer periphery that bulges in the outer radial direction.
The seat ring 8 is fixed to the valve seat 3 by pressing a fixing metal ring 11 against the inner circumferential wall of the recess 6. Further, in the third embodiment shown in FIG. 4, a thin fixing ring 7 is used, and a fixing metal ring 11 that is not connected to the seat ring 8 is attached to the outer peripheral edge of the fixing ring 7.
is provided.

Also in these embodiments, when the valve body 5 presses the seat ring 8, the metal ring 9 is compressively deformed and bulges in the inner diameter direction, so the metal ring 9 comes into pressure contact with the seal portion 5b of the valve body 5 and seals the fluid. It becomes like this.

In the fourth embodiment shown in FIG. 5 and the fifth embodiment shown in FIG. 6, resin rings 12 and 13 made of synthetic rubber or the like are provided as elastic rings. That is,
A bottomed cylindrical boulder 15 having a communication hole 14 at the bottom is fixed to the concave portion 6 of the valve seat 3 by welding or press fitting, and a trapezoidal boulder 15 is formed in the holder 15 in cross section with a thick inner side and a thin outer side. A cross section V is formed on the resin ring 12 and the upper surface.
A resin ring 13 having a letter-shaped annular groove 13a is loaded. Reference numeral 16 designates a seat ring having a seat surface 16a superimposed above the resin ring 12, and is formed in a trapezoidal cross section with a thin inner side and a thick outer side. A seat ring 17 has a seat surface 17a superimposed above the resin ring 13, and is engaged in the annular groove 13a.

18 is a seat ring 16 that is fitted onto the inner peripheral surface of the boulder 15.
．． This is a retaining ring that locks 17.

Therefore, when the valve body 5 moves forward in the direction of the partition wall 1 and presses the seat ring 16.17, the resin ring 12.13 is compressively deformed and bulges in the inner diameter direction, so that the resin ring 12.13 is compressed and deformed and bulges in the inner diameter direction. Becomes to seal.

〔Effect of the invention〕

As explained above, according to the present invention, the seat ring on which the valve body is seated is elastically deformed so as to bulge in the inner diameter direction, and the valve body is partitioned through the elastic ring through which a part of the valve body is inserted. Since it is provided on the wall, the seat ring and the elastic ring can be brought into pressure contact with the valve body by moving the valve body forward with respect to the partition wall.

Therefore, it is possible to seal between the valve body and the partition wall at two places, the seat ring and the elastic ring, and even if the seat surface is damaged and leakage occurs between the seat ring and the valve body, the elastic ring Since the valve can be reliably closed, leakage can be prevented from increasing rapidly. As a result, the life of the valve device can be extended.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a main part showing a first embodiment of a valve device according to the present invention, FIG. 2 is a sectional view similarly showing a closed state, and FIG.
6 to 6 are sectional views of main parts showing second to fifth embodiments. 1...Partition wall, 5...Valve body, 8...Seat ring, 9...Metal ring, 12.13...Resin ring, 16.17...Seat ring.

Claims (1)

[Claims] A seat ring having a seat surface on which the valve body is seated is elastically deformed so as to bulge in the inner diameter direction as it is pressed in the axial direction, and a portion of the valve body is inserted through the elastic ring to the valve body. A valve device characterized in that it is installed on a partition wall.