JPH11218234A - Valve element of butterfly valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the valve element of a butterfly valve which generates no deformation of a core metal when the core metal of the valve element is processed, and reduces the pressure loss of the valve element after the lining formation as small as possible. SOLUTION: To the upper and the lower sides of a core member 15 for valve element boss parts 20 and 21 having stem insertion holes 18 and 19 are provided, and an opening 24 is formed to the core member 15 positioning between the boss parts 20 and 21. At the same time, the upper and the lower stem insertion holes 18 and 19 are provided allowable to penetrate almost in the linear direction each other through the opening 24, and furthermore, this opening 24 is filled with a covered material such as a resin, and the outer periphery of the core member 15 is covered by the covered material, in the valve element of a butterfly valve.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a butterfly valve body lined with a coating material such as a resin.

[0002]

2. Description of the Related Art In general, a center type butterfly valve is provided with a ring-shaped seat mounted on a body, and a disc-shaped valve body provided with stems on the inner periphery of the seat so as to be rotatable. Since the liquid-contacting components of this valve are only the seat and the valve body, the liquid-contacting components can be applied to a corrosive fluid by using a material having high corrosion resistance.

[0003] In this type of valve, rubber or fluororesin is used for the seat, whereas metal is generally used for the valve body. Therefore, a resin-lined valve body is used for a corrosive fluid in which metal cannot be used. Is used.

[0004] The valve body of the resin lining employs a structure reinforced with a metal core to maintain the pressure resistance, and various structures of the metal core have been proposed. The following are known as connection structures between a cored bar and upper and lower stems.

In the valve body 6 shown in FIG. 10, the upper and lower stem holes 2 and 3 of the cored bar 1 are formed in a blind hole shape, and the stems 4 and 5 are mounted in the blind hole stem holes 2 and 3, respectively. In this type of valve body 6, since the stem holes 2 and 3 are formed in a blind hole shape, the central portion of the valve body 6 can be formed in a thin shape. Can be widened. In the figure, reference numeral 6a denotes a resin lining of the metal core 1.

The valve element 7 shown in FIG. 11 has a stem hole above and below the core bar 13 as one through hole 8, and the inner peripheral surfaces of the connecting portions 9 and 10 for transmitting the operating torque of the stem are formed in a square or two by broaching. A square hole processing portion such as a surface shape is formed. In addition, the valve body 7 has a core metal 13 with a resin lining 7b.

[0007]

However, FIG.
In the valve element 6 shown in FIG. 5, since the stem holes 2 and 3 of the cored bar 1 are vertically divided, the square hole processing portion 11 for transmitting the operating torque
When molding a, since the core 12 is processed by the press 12 as shown in FIGS. 12 and 13, the cored bar 1 may be deformed during the processing as shown in FIG. In some cases, the center accuracy of No. 3 was deteriorated and sheet leakage occurred.

In the valve element 7 shown in FIG. 11, since the upper and lower stem holes are penetrated as through holes 8, when forming the square hole processing portion 11b, the connecting portions 9, 10 of the stem holes are pressed. Since it can be processed with a broach that can be processed with a smaller force, there is no deformation of the metal core 13 as in the processing shown in FIG. 10, but since the central portion of the valve body 7 is thick, as shown in FIG. There is a problem that the flow path 14a at the time of full opening becomes smaller and the pressure loss increases accordingly. In particular, when the nominal diameter of the butterfly valve 14 is 65A or less, the problem becomes more serious as the nominal diameter becomes smaller.

SUMMARY OF THE INVENTION The present invention has been developed to solve the above-mentioned problems. It is an object of the present invention to form a lining without deforming the metal core when processing the metal core of the valve body. An object of the present invention is to provide a butterfly valve valve body in which pressure loss due to a later valve body is minimized.

[0010]

In order to achieve the above object, a butterfly valve of the present invention is provided with a boss having stem insertion holes above and below a core for a valve, and a boss between the bosses. An opening is formed in the core material located, and the upper and lower stem insertion holes are provided so as to be able to penetrate in a substantially linear direction through the opening, and the opening is filled with a coating material such as a resin. In addition, the outer periphery of the core is covered with this covering material or another covering material such as resin.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a valve body of a butterfly valve according to the present invention will be described with reference to FIGS.
In FIG. 1, the core material 15 has a substantially disk shape,
The material of the core material 15 is formed of a metal such as stainless steel, brass, bronze, or cast iron, and is integrally formed by means such as casting, forging, or pressing. The core material 15 may be other than a metal material, and may be any rigid material that functions as a reinforcing core material for the valve body, and is appropriately selected according to the implementation. Further, the outer peripheral edge of the core material 15 is preferably formed in a substantially arc shape.

A boss 2 having stem insertion holes 18 and 19 for transmitting the rotational operation force by inserting the stems 17a and 17b of the butterfly valve 16 above and below the core material 15.
0 and 21 are provided, and the boss portions 20 and 21 have a substantially cylindrical shape. On the inner peripheral surfaces of the insertion holes 18 and 19, a square shape for connecting the connecting portion 22 such as a square surface or two surfaces formed at the ends of the upper and lower stems 17a and 17b or a serration portion, one surface processing, two surfaces. A processing surface portion 23 such as processing or serration processing is formed.

The core material 1 connecting the boss portion 20 and the boss portion 21
An opening 24 is formed in the core 15 located between the bosses 20 and 21 in a direction intersecting the diameter direction of the boss 5. When the core material 15 is formed by a casting method, the opening 24 is a cast hole. The opening 24 is an opening space for allowing the stem insertion holes 18 and 19 to penetrate in a linear direction.
Since there is a space between them, the stem insertion hole 18,
It is configured to be able to penetrate through an insertion member such as a broach from one of them.

The opening 24 is formed with a coating material 2 such as resin.
5 and cover the outer peripheral surface of the core material 15 to form a lining valve body. Although the covering material 25 is made of a resin material, other materials such as an elastic material such as rubber and a metal having a lower melting point than the core metal can be selected. When the coating material 25 is made of a resin material, ethylene tetrafluoride resin (PTFE), polyphenylene sulfide (PPS), PFA, nylon or other resin is appropriately selected, and lining is performed by means such as injection molding. In this case, the thickness of the center portion and the like lining the core material 15 is such that the flow path does not become small when the valve is fully opened, and that the thickness of the valve body does not affect the strength. In the above example, the coating material 25 to be filled in the opening 24 and the lining of the core material 15 are formed simultaneously with the same material. Or the like, and then the entire valve may be coated with a coating material of a material such as a corrosion-resistant resin.

Further, since the opening 24 is formed at the central portion of the core member 15, the weight of the core member 15 can be reduced, and the coating material 25 is integrated by the opening 24, so that the stress caused by the opening and closing of the valve is achieved. There is no fear that the coating material 25 receiving the same will peel off from the core material 15. In the figure, reference numeral 26 denotes the coating material 2
A sealing ridge portion 27 formed on the outer peripheral edge of 5 is a flow path portion of the butterfly valve 16.

Next, the operation of the above embodiment will be described.
In the state of the core metal 15 shown in FIG.
When the connecting portion 23 on the inner peripheral surface of each of the inner and outer surfaces 8 and 19 is broached, as shown in FIGS.
9 is a space by the opening 24, so that the broach 28 can pass through the insertion holes 18 and 19 in a substantially linear direction. Therefore, the stem insertion holes 18 and 19 can be processed by the broach 28 which can be processed with a smaller force than the press, and there is no possibility that the core material 15 is deformed by the influence of the processing, and the processing can be performed reliably.

Further, the opening 24 is formed with a coating material 25 such as resin.
And the outer peripheral surface of the core material 15 is covered with the coating material 25. Therefore, there is no possibility that the central portion of the valve body becomes thick as in the conventional example in FIG. Similarly to the structure shown in FIG.
9, the flow path 27 when the valve is fully opened is widened as shown in FIG. 9, and the pressure loss can be reduced accordingly. Further, the coating material 25 is integrated with the front and back surfaces of the core material 15 by the opening 24, and the coating material 25 does not peel off from the core material 15 even after long-term use.

[0018]

As is clear from the above, according to the present invention, in the state of the core, the upper and lower stem insertion holes penetrate, so that, for example, the processing of a square hole or the like by a broach can be performed. As a result, there is no possibility that the core material is deformed by press working as in the related art, the center accuracy of the stem insertion hole is reliably maintained, and the sealing function of the valve body can be effectively exhibited.

Further, the central portion of the valve body is not formed thick as in the prior art. Therefore, the flow path when the valve is fully opened is widened, and the pressure loss can be minimized. Even if the nominal diameter becomes small, there is a remarkable effect that a sufficient flow path can be ensured when the valve is fully opened.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a core material according to the present invention.

FIG. 2 is a half sectional view of FIG.

FIG. 3 is a cross-sectional view of FIG.

FIG. 4 is a half sectional view of a valve body according to the present invention.

FIG. 5 is a cross-sectional view of FIG.

FIG. 6 is a plan view of FIG. 4;

FIG. 7 is a cross-sectional view illustrating a state in which the core material according to the present invention is broached.

FIG. 8 is a front sectional view of FIG. 7;

FIG. 9 is a front view of a butterfly valve provided with a valve body according to the present invention.

FIG. 10 is a cross-sectional view showing an example of a conventional resin-lined valve element.

FIG. 11 is a sectional view showing another example of a conventional resin-lined valve body.

12 is a cross-sectional view showing a state where the conventional core material of FIG. 10 is pressed.

FIG. 13 is a front view of FIG.

FIG. 14 is a front view of a butterfly valve to which the valve body of FIG. 11 is attached.

[Explanation of symbols]

 15 Core material 16 Butterfly valve 17a, 17b Stem 18, 19 Stem insertion hole 20, 21 Boss 23 Work surface 24 Opening 25 Coating material

Claims (1)

[Claims] A boss having a stem insertion hole is provided above and below a valve body core material, an opening is formed in a core material located between the boss portions, and the upper and lower stem insertion holes are connected to each other by the upper and lower stem insertion holes. It is provided so as to be able to penetrate in a substantially linear direction through the opening, and further,
A valve body for a butterfly valve, wherein the opening is filled with a covering material such as a resin, and the outer periphery of a core material is covered with the covering material or another covering material such as a resin.