JP2932420B2 - Butterfly 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 butterfly valve having a seat ring made of synthetic rubber and used for controlling piping of various fluids.

[0002]

2. Description of the Related Art A synthetic rubber seat ring of a conventional butterfly valve used for controlling various fluid pipes is known to be formed of one kind of synthetic rubber. For synthetic rubber seat rings of butterfly valves, hardness, tensile strength, tear strength, elongation, compression elasticity, abrasion resistance, oil resistance, chemical resistance, temperature resistance, gas permeability resistance, etc. Various characteristics are required. However, these characteristics are not required for all portions of the seat ring, and required characteristics are different depending on the portions. In addition, a characteristic that is suitable for a certain part is inappropriate for another part, and thus this characteristic cannot be provided in some cases.

[0003]

For this reason, a seat ring formed of one kind of synthetic rubber has unique characteristics required for the synthetic rubber, and therefore is expensive and expensive. Nevertheless, the quality, durability and reliability required for the valve were insufficient. In order to compensate for these drawbacks, the shape of the seat ring may be complicated or a mandrel may be buried, but this is not sufficient and the price is higher.

[0004] The problem to be solved by the present invention is that the conventional synthetic rubber seat ring of the butterfly valve has a disadvantage that not all parts have suitable characteristics for that part, that it is expensive, that the quality is high. The durability and reliability are insufficient, and the present invention aims to provide a butterfly valve that solves these conventional problems at once.

[0005]

Means for Solving the Problems To achieve the above object,
Therefore, the present invention has a shaft mounting portion for mounting a stem vertically.
Attach a seat ring to the inner peripheral surface of the cylindrical body.
A disc that rotates by stem operation on the inner peripheral surface of the seat ring
In the butterfly valve that can be opened and closed freely,
The tring consists of a non-wetted part that makes fixed contact with the body,
-Fixed contact part for fixed contact and liquid contact with other piping parts
Contact, liquid contact, sliding contact with stem, stem and disc
The three types of synthetic rubber of the part are molded integrally, and these three types
Synthetic rubber of a type that matches the action received and the required properties
It is noted that the seat ring was molded integrally using
This is a butterfly valve.

[0006]

The seat ring of the butterfly valve according to the present invention has a fixed contact with a non-wetted portion constituting the seat ring.
For each part of the sliding contact and liquid contact part with the part, the action such as compression, tension, torsion, tear, etc. and the required properties such as wear resistance, oil resistance, chemical resistance, temperature resistance etc. Using synthetic rubber suitable for
Since two or more types of synthetic rubber are integrally molded, there is no need to form the entire body with synthetic rubber with unnecessarily expensive and unique characteristics, resulting in a seat ring with high quality, durability and reliability. It is not necessary to make a special shape or supplement the characteristics with a mandrel.

[0008]

FIG. 1 is a perspective view showing an embodiment of a butterfly valve according to the present invention, partially cut away, and FIG. 2 is a view showing a seat ring of the butterfly valve shown in FIG. 1 in a plane including a center line of a stem. FIG. 3 is a partially cutaway perspective view showing the half cut surface of FIG. 2 of the seat ring of FIG. 2, and FIG. 4 is a half cut surface of the seat ring of FIG. It is the fragmentary sectional view which showed the half cut surface which is perpendicular to it. 1 to 4, reference numeral 1 denotes a butterfly valve, 2
Is a seat ring, 3 is a body, 4 is a disc, and 5 is a stem.

In FIG. 1, a butterfly valve 1 is opened and closed by rotating a stem 5 and opening and closing the inner diameter of a seat ring 2 by these fixed disks 4. A, B,... Of the seat ring 2 in FIG.
Each of the parts indicated by using the symbol H is required to have properties as shown in the following table.

[0010]

[Table 1]

The seat ring 2 of the butterfly valve 1 of this embodiment is formed by integrally molding three types of synthetic rubber, X, Y, and Z shown in FIG. 1 to FIG. solid was and, X is a risk of liquid contact and the fixed contact with the body 3 or other plumbing components (such as pipe flanges)
Is for constant contact site, Y is for sliding contact-wetted parts in contact to and wetted sliding stem 5 or disuccinimidyl 4, Z is no risk of liquid contact to secure contact with the body 3 non-close Table 1 above for liquid sites
As shown in, X is A and B, Y is C to F,
Z is used in the G and H parts, and is a synthetic rubber having characteristics required for each part.

Next, the operation of the seat ring 2 of the butterfly valve 1 of the present invention shown in FIGS. 1 to 4 will be described. The seat ring 2 divides the parts constituting the seat ring 2 into eight parts A, B,... H as described above, and receives these parts such as actions such as compression, tension, torsion, and tear, Required abrasion resistance, oil resistance,
Considering properties such as chemical resistance and temperature resistance, these eight parts are divided into three groups of A and B, C to F, G and H, and a suitable synthetic rubber is selected for each group. Since these three types of synthetic rubbers are integrally formed and formed, there is no need to form the entirety with unnecessary and expensive synthetic rubbers having unique characteristics, and the seat ring 2 has high quality, durability and reliability. Therefore, there is no need to form the seat ring 2 into a special shape or to supplement the characteristics with a mandrel.

[0013]

Since the seat ring of the butterfly valve according to the present invention is constructed as described above, the following excellent effects can be obtained. First, since an inexpensive synthetic rubber can be used depending on a part, an inexpensive seat ring can be manufactured. Further, since each part of the seat ring is made of synthetic rubber suitable for the action to be received and the required characteristics, the valve has excellent reliability and durability. Further, by selecting a synthetic rubber material to be used, it is possible to meet strict specifications including test conditions.

[Brief description of the drawings]

FIG. 1 is a perspective view of a butterfly valve according to an embodiment of the present invention, which is partially cut away.

FIG. 2 is a perspective view of the seat ring shown in FIG. 1 cut in half at a plane including a center line of a stem.

FIG. 3 is a partial cross-sectional view showing a half cut surface of FIG. 2 of the seat ring of FIG. 2;

FIG. 4 is a partial cross-sectional view showing a half cut surface of the seat ring of FIG. 2 which is perpendicular to the half cut surface of FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Butterfly valve 2 Seat ring 3 Body 4 Disk 5 Stem A, B, C, D, E, F, G, H Parts of seat ring X, Y, Z Three types of synthetic rubber

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F16K 1/226

Claims (1)

(57) [Claims] 1. A shaft mounting part for vertically mounting a stem.
Attach a seat ring to the inner peripheral surface of the cylindrical body.
A disc that rotates by stem operation on the inner peripheral surface of the seat ring
In the butterfly valve that can be opened and closed freely,
The tring consists of a non-wetted part that makes fixed contact with the body,
-Fixed contact part for fixed contact and liquid contact with other piping parts
Contact, liquid contact, sliding contact with stem, stem and disc
The three types of synthetic rubber of the part are molded integrally, and these three types
Synthetic rubber of a type that matches the action received and the required properties
It is noted that the seat ring was molded integrally using
Butterfly valve to symbolize.