JPH0449415Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a device for preventing foreign matter from entering the seal portion of a spherical valve.

[Conventional technology]

Examples of conventional spherical valves include those shown in Figures 3 and 4.
There is something like the one shown in the figure. That is, in these figures, 1 is a valve body having an inlet side flow path 1a and an outlet side flow path 1b, 2 is a sphere having a flow path 2a inserted into this valve body 1, and 3 is the valve body. an annular sheet inserted between 1 and the sphere 2, 4;
Reference numeral 4 denotes a non-metallic annular elastic seal body, the base of which is an annular mounting groove 3 recessed in the slope of each of the annular sheets 3, 3 on the spherical body 2 side.
a, 3a, and its tip is in sliding contact with the outer circumferential surface of the sphere 2. 5, 5 are the seal bodies 4, 4 and the valve body 1;
The seal bodies 4, 4 are always in sliding contact with the spherical body 2 by means of a spring inserted between the stepped portions of the annular sheets 3, 3, and the spherical body 2, thereby closing the gaps 6, 6 between the annular sheets 3, 3 and the spherical body 2, thereby fulfilling the sealing function. I am encouraging you to do so. Reference numerals 7, 7 are openings exposed on the flow path side of the gaps 6, 6, the width of which is relatively small when the spherical valve is in the closed state (see Fig. 3), and wide when the spherical valve is in the open state (see Fig. 4). When,
It is relatively large.

In addition, in FIG. 4, since the inlet side and the outlet side have the same structure, only the lower part of the inlet side is shown in detail.

In this way, this type of spherical valve uses a sealing mechanism that prevents leakage by using non-metallic elastic seal bodies 4, 4 placed in the gaps 6, 6 between the sphere 2 and the annular sheets 3, 3. However, since there are gaps 6, 6 and openings 7, 7, the structure is such that foreign matter can easily get mixed in.

The elastic seal bodies 4, 4 are quite weak in terms of wear resistance due to contamination with foreign matter, but on the other hand, they have many advantages in terms of sealing performance, etc., so they are effective under the condition that they are used in relatively clean conditions. It is widely used as a method.

[The problem that the idea aims to solve]

However, such conventional spherical valves are usually kept open until the installation is completed to avoid damaging the sealing surfaces on which the sealing bodies 4, 4 of the sphere 2 slide during transportation and pipeline construction. state). During this period, there is a very high possibility that foreign substances such as welding slag, sand, and dust will enter the pipeline, especially during pipeline construction, so it is practical to prevent these foreign substances from entering the pipeline during on-site work. It is very difficult to do so.

Therefore, in this case, since the openings 7, 7 are relatively large, foreign matter that has entered the pipeline is accumulated in the gaps 6, 6 through the openings 7, 7, and then when the sphere 2 is rotated. In this case, these foreign substances may become entangled in the seal portions, causing damage such as breakage or abrasion of the seal bodies 4, 4 and the sphere 2, and as a result, fluid may leak from the seal portions. Therefore, it becomes necessary to replace the seal bodies 4, 4, or in some cases, replace the valve itself.

In particular, for large pipeline valves and valves that are buried underground, removing the valve once installed in the pipeline not only requires interruption of operation, but also requires a large amount of labor and expense. Damage to the seal body 4 is fatal to the valve. Furthermore, in the case of a directly buried fully welded valve, there was a problem in that the seal body 4 could not be replaced at all.

The present invention was developed with a focus on such conventional problems, and it prevents foreign substances from entering the sealing part.
It is an object of the present invention to provide a device for preventing foreign matter from entering a seal portion of a spherical valve, which prevents damage to a seal body.

[Means to solve the problem]

In order to achieve this object, the present invention includes a valve body, a sphere having a flow path inserted into the valve body, a seat inserted between the valve body and the sphere, and a valve body and a sphere inserted between the valve body and the sphere. In a spherical valve comprising a sealing body attached to the sheet so as to close a gap with the sphere, an elastic lip is arranged on the sphere so as to cover at least approximately the lower half circumference of the opening exposed on the flow path side of the gap. It was established.

[Effect]

Even if foreign matter mixed into the pipeline tries to enter the gap, the opening of the gap is covered with an elastic lip, so the intrusion is prevented.
It does not reach the seal portion where the seal body is disposed, and as a result, damage to the seal body and the sphere is prevented.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

Note that parts and parts that are the same as before are given the same reference numerals.

In FIGS. 1 and 2, 1 is a valve body having an inlet side flow path 1a and an outlet side flow path 1b, 2 is a sphere having a flow path 2a inserted in the valve body 1, and 3, 3 are The annular sheets 4, 4 inserted between the valve body 1 and the spherical body 2 are made of non-metallic material and are annular elastic sealing bodies, the base of which is located on the spherical body 2 side of each of the annular sheets 3, 3. The spherical body 2 is fitted by being inserted into annular mounting grooves 3a, 3a recessed in the slope of the spherical body 2, and its tip is in sliding contact with the outer circumferential surface of the spherical body 2. 5, 5 are the seal bodies 4, 4
and the stepped portion of the valve body 1, the sealing bodies 4, 4 are always in sliding contact with the spherical body 2, and the gap 6 between the annular seats 3, 3 and the spherical body 2 is reduced.
6 and is biased to fulfill its sealing function. 7, 7 are openings exposed on the flow path side of the gaps 6, 6, the width of which is relatively small when the spherical valve is in the closed state (see Fig. 2), and is relatively small when the spherical valve is in the closed state (see Fig. 1). At that time, it is relatively large.

The above structure is the same as before.

The spherical body 2 has elastic lips 8, 8 that cover approximately the lower half circumference of the openings 7, 7 exposed on the flow path side of the gaps 6, 6 when the spherical valve is in the open state.
is installed.

The bases of the elastic lips 8, 8 are fixed to the inner circumferential surface of the channel 2a of the sphere 2 via a holding plate 9 with a mounting bolt 10.

Since the inlet and outlet sides have the same structure, FIG. 1 shows only the lower part of the inlet side in detail.

It goes without saying that the material, thickness, length, etc. of the elastic lips 8, 8 are appropriately determined so that the sphere 2 can rotate smoothly.

With this configuration, since the spherical valve is normally in an open state during normal transportation and pipeline construction, foreign matter mixed into the pipeline may enter the gaps 6, 6 where the seal bodies 4, 4 are arranged. Even if an attempt is made to do so, the openings 7, 7 exposed on the flow path side of the gaps 6, 6 are covered by the elastic lips 8, 8, so that the intrusion is prevented, and the seal portion where the seal 4 is placed is prevented from entering. Not enough. As a result, even if the sphere 2 is subsequently rotated, foreign matter will not be caught in the seal portion, and damage to the seal bodies 4, 4 can be prevented, and damage to the sphere 2 can also be prevented. It is.

Similarly, it is naturally possible to prevent foreign matter from entering the seal portion during pipeline operation.

As described above, since damage to the seal body 4 and the sphere 2 can be prevented, the life and reliability of the spherical valve can be improved.

In addition, since most of the foreign matter enters the gap 6 at approximately the lower half circumference of the opening 7, in the above embodiment the elastic lip 8 is disposed to cover approximately the lower half circumference of the openings 7, but the spherical valve It may be necessary to move it depending on the direction in which it is attached, and it may also be extended to the upper half of the circumference, and it goes without saying that it is preferable to dispose it over the entire circumference.

〔effect〕

As explained above, according to the present invention, it is possible to prevent foreign matter from entering the seal part, prevent damage to the seal body and the sphere, and as a result, extend the life of the valve and improve its reliability. This effect can be obtained.

[Brief explanation of the drawing]

Fig. 1 is an enlarged cross-sectional view of the main part of Fig. 2 in the open state, Fig. 2 is a cross-sectional view of the spherical valve in the closed state showing an embodiment of the present invention, and Fig. 3 is a spherical valve showing the conventional example. FIG. 4 is a sectional view of the valve in the closed state, and FIG. 4 is an enlarged sectional view of the main part of FIG. 3 in the open state. 1... Valve body, 2... Sphere, 2a... Channel, 3
...Annular sheet, 4...Seal body, 6...Gap,
7...Opening, 8...Elastic lip.

Claims (1)

[Scope of utility model registration request] a valve body, a sphere having a flow path inserted into the valve body, a seat interposed between the valve body and the sphere, and the sheet so as to close a gap between the seat and the sphere. A spherical valve comprising a seal body attached to a spherical valve, wherein an elastic lip is provided on the spherical body so as to cover at least approximately the lower half circumference of the opening exposed on the flow path side of the gap. Foreign matter prevention device.