JP6811104B2 - Butterfly valve and butterfly valve manufacturing method - Google Patents

Description

The present invention relates to a butterfly valve and a method for manufacturing a butterfly valve .

Conventionally, a tubular cast iron valve box, a valve seat formed on the inner peripheral surface of the valve box, a valve body stored in the valve box and seatable on the valve seat, and the valve box and the valve body are connected. A butterfly valve provided with a valve rod and in which the valve body rotates about the valve rod as a central axis is known (see, for example, Patent Document 1). The butterfly valve described in Patent Document 1 is connected to a pipeline through which a fluid flows, and when the valve body is seated on the valve seat, the fluid flowing through the pipeline is blocked.

The valve seat on which the valve body is seated is made of, for example, stainless steel, and the valve seat is usually formed on the inner peripheral surface of a cast iron valve box. Specifically, the valve seat is formed by scraping a part of the inner peripheral surface of the valve box, sequentially welding nickel metal and stainless steel to the scraped portion, and cutting the surface of the stainless steel. To.

Japanese Unexamined Patent Publication No. 2011-22470

However, in order for the valve body to sit on the valve seat and reliably block the fluid flowing through the pipeline, the cutting process applied to the stainless steel surface must be precise and requires a high degree of expertise and experience. become. Further, in order to form the stainless steel valve seat on the inner peripheral surface of the cast iron valve box, a plurality of steps are required from the step of cutting the valve box to the step of cutting the surface of the stainless steel, and as a result. , Long hours of work are required to form the valve seat in the valve box. That is, there is a problem that the valve seat cannot be easily formed on the inner peripheral surface of the valve box.

An object of the present invention is to provide a butterfly valve and a method for manufacturing a butterfly valve, which can easily form a valve seat on the inner peripheral surface of a valve box.

In order to achieve the above object, the butterfly valve of the present invention has a fluid inflow port into which a fluid flows, a fluid passing surface through which the fluid passes , and a fluid flowing in from the fluid inflow port and passing through the fluid passing surface . A valve box having a fluid outlet, a valve seat receiving portion formed on the fluid passage surface between the fluid inlet and the fluid outlet, and a ring-shaped valve seat attached to the valve seat receiving portion. The valve seat receiving portion includes a member, and the valve seat receiving portion is formed adjacent to the female threaded portion to which the valve seat member is attached and the fluid outlet side of the female threaded portion, and is formed from the fluid passage surface to the central axis of the valve box. The valve seat member is formed on the outer peripheral surface of the valve seat member and has a male screw portion corresponding to the female thread portion and an inner peripheral surface of the valve seat member. a valve seat which is, has, and side portions positioned in the fluid flow outlet side when mounted to said valve seat receiving said valve seat member, said male screw portion is screwed into the female screw portion At the same time, the side surface portion is attached to the valve seat receiving portion by abutting on the protruding portion .
Further, in order to achieve the above object, the method for manufacturing a butterfly valve of the present invention has a fluid inflow port into which a fluid flows, a fluid passage surface through which the fluid passes, and a fluid passage surface inflow from the fluid inflow port. A valve box having a fluid outlet through which the passed fluid flows out, and a valve seat receiving portion formed on the fluid passing surface between the fluid inlet and the fluid outlet, and attached to the valve seat receiving portion. A ring-shaped valve seat member is provided, and the valve seat receiving portion is formed adjacent to a female threaded portion to which the valve seat member is attached and the fluid outlet side of the female threaded portion, and is described from the fluid passage surface. The valve seat member has a protruding portion that protrudes with respect to the central axis of the valve box, and the valve seat member is formed on the outer peripheral surface of the valve seat member and has a male threaded portion corresponding to the female threaded portion, and the valve seat member The valve seat member has a valve seat portion formed on an inner peripheral surface and a side surface portion located on the fluid outlet side when attached to the valve seat receiving portion, and the valve seat member has the male screw portion. In a method for manufacturing a butterfly valve, which comprises screwing into a female thread portion and attaching the side surface portion to the valve seat receiving portion by abutting against the protruding portion, the valve seat member is attached to the valve box. It is characterized by having an insertion step of inserting the fluid, a screwing step of screwing the male threaded portion into the female threaded portion, and an abutting step of contacting the side surface portion with the protruding portion.

According to the present invention, a valve seat can be easily formed on the inner peripheral surface of the valve box.

FIG. 1A is a front view of the butterfly valve, and FIG. 1B is a side view of the butterfly valve, which is a schematic view of the butterfly valve according to the embodiment of the present invention. It is a perspective view of the valve box in FIG. It is sectional drawing which follows the AA line of the butterfly valve of FIG. It is an enlarged view of the area C in FIG. It is a perspective view of the valve seat member in FIG. It is sectional drawing which follows the line BB of the butterfly valve of FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

1A and 1B are schematic views of a butterfly valve 1 according to an embodiment of the present invention, FIG. 1A is a front view of the butterfly valve 1, and FIG. 1B is a side view of the butterfly valve 1. Is.

The butterfly valve 1 of FIG. 1 includes a valve box 2 made of cast iron, a substantially disk-shaped valve body 4 housed in the valve box 2, closing members 8a and 8b, and a valve seat member 12 made of stainless steel. The valve box 2 has a tubular shape having a central axis O, and is arranged in the valve box outer peripheral surface 2a along the circumferential direction and on the central axis O side of the valve box outer peripheral surface 2a and in the valve box through which a fluid passes. It has a peripheral surface 2b (fluid passage surface). The inner diameter of the valve box 2 may change along the central axis O. Further, each of both ends of the valve box 2 has flange portions 5a and 5b. The flange portions 5a and 5b are connected to a flow path through which a fluid flows, for example, a water pipe. Specifically, a flange portion is attached to the water pipe, and the flange portion attached to the water pipe and the flange portions 5a and 5b are connected by bolts, nuts and the like. In the present embodiment, it is assumed that the butterfly valve 1 is connected to the water pipe, and the water flowing through the water pipe flows in from the fluid inlet M on the flange portion 5a side and flows out from the fluid outlet N on the flange portion 5b side. And.

The valve body 4 includes a valve shaft insertion portion (not shown) for inserting the valve shaft 3 described later. The valve shaft 3 penetrates the valve body 4 via the valve shaft insertion portion and protrudes from both ends of the valve shaft insertion portion. The closing members 8a and 8b are arranged on the outer peripheral surface 2a of the valve box in a direction orthogonal to the central axis O, and hold both ends of the valve shaft 3 protruding from both ends of the valve shaft insertion portion. That is, the valve shaft 3 is fixed by the closing members 8a and 8b, and the valve body 4 rotates about the valve shaft 3.

FIG. 2 is a perspective view of the valve box 2 in FIG.

The valve box 2 of FIG. 2 is provided with insertion holes 7a and 7b, and the insertion holes 7a and 7b are arranged in a direction orthogonal to the central axis O. Both ends of the valve shaft 3 protruding from both ends of the valve shaft insertion portion are held by the closing members 8a and 8b via the insertion holes 7a and 7b. That is, the butterfly valve 1 is assembled by sequentially inserting the valve shaft 3 into the insertion hole 7a, the valve shaft insertion portion, and the insertion hole 7b, and attaching the closing members 8a and 8b to both ends of the valve shaft 3.

FIG. 3 is a cross-sectional view taken along the line AA of the butterfly valve 1 of FIG.

The butterfly valve 1 of FIG. 3 includes a rotation shaft P orthogonal to the central axis O and when the valve body 4 rotates, and a valve seat member 12 is provided on the fluid outlet N side of the rotation shaft P. The valve seat member 12 is attached to a valve seat receiving portion 10 provided on the inner peripheral surface 2b of the valve box.

FIG. 4 is an enlarged view of the region C in FIG. 3, and is a diagram for explaining the periphery of the valve seat receiving portion 10.

The valve seat receiving portion 10 of FIG. 4 projects from the female screw portion 10a for attaching the valve seat member 12 and the valve box inner peripheral surface 2b toward the central axis O side, and determines the position where the valve seat member 12 is attached. It has a positioning portion 10b (protruding portion) . The valve seat member 12 of the present embodiment has a ring shape, has a valve seat central axis Q, and has a valve seat member outer peripheral surface 12a along the circumferential direction of the valve seat member 12 and a valve seat member outer peripheral surface 12a. The inner peripheral surface 12c of the valve seat member arranged on the Q side of the valve seat central axis, and the contact portion 12b (side surface portion) that comes into contact with the positioning portion 10b when the valve seat member 12 is attached to the valve seat receiving portion 10. A male screw portion 12e corresponding to the female screw portion 10a is formed on the outer peripheral surface 12a of the valve seat member (FIG. 5). A recess is formed in either the contact portion 12b or the positioning portion 10b, but in the present embodiment, it is assumed that the recess is formed in the contact portion 12b. An O-ring 14 (water blocking member) is fitted in the recess, and the cross-sectional shape of the O-ring 14 not fitted in the recess is circular, but the O-ring 14 is fitted in the recess and the valve seat member 12 is When attached to the valve seat receiving portion 10 and the abutting portion 12b abuts on the positioning portion 10b, the O-ring 14 is deformed, and the cross-sectional shape of the O-ring 14 becomes, for example, an ellipse.

Returning to FIG. 3, the valve box 2 is configured such that the inner diameter of the valve box 2 from the end portion on the fluid inflow port M side to the valve seat receiving portion 10 is larger than the outer diameter (maximum diameter) of the valve seat member 12. Has been done. Therefore, in order to attach the valve seat member 12 to the valve seat receiving portion 10, the valve seat member 12 is first inserted into the valve box 2 from the fluid inflow port M so that the central axis O and the valve seat central axis Q overlap. Then, the male screw portion 12e is inserted until it comes into contact with the female screw portion 10a (insertion step) . Next, the male screw portion 12e is screwed into the female screw portion 10a until the contact portion 12b abuts on the position determining portion 10b ( screw step) . When the valve seat member 12 is screwed into the valve seat receiving portion 10 and the contact portion 12b abuts on the position determining portion 10b (contact step) , the attachment of the valve seat member 12 to the valve seat receiving portion 10 is completed. ( Butterfly valve manufacturing method).

The inner peripheral surface 12c of the valve seat member has at least a part thereof having a tapered portion 12d that is inclined with respect to the central axis O so that the valve seat member 12 expands in diameter from the fluid outlet N toward the fluid inlet M. When the outer edge portion of the valve body 4 comes into contact with the tapered portion 12d, the water flowing in from the fluid inflow port M is blocked by the valve body 4. The outer edge of the valve body 4 may be subjected to a rubber lining process, or may be metal-processed with a stainless metal, aluminum, or the like.

FIG. 6 is a cross-sectional view taken along the line BB of the butterfly valve of FIG.

The butterfly valve 1 of FIG. 6 includes a valve shaft 3, and the valve shaft 3 supports the valve body 4 via a valve shaft insertion portion. The outer edge of the valve body 4 comes into contact with the valve seat member 12, and the outer edge of the valve body 4 is valved from a state in which the water flowing in from the fluid inflow port M does not flow out from the fluid outflow port N (hereinafter, referred to as "valve closed state"). The water flowing in from the fluid inflow port M does not come into contact with the seat member 12, and the water flows out from the fluid outflow port N (hereinafter referred to as "valve open state") by rotating or opening around the valve shaft 3. It rotates about the valve shaft 3 from the valve state to the valve closed state. In the present embodiment, the route through which the valve body 4 passes when rotating from the valve closed state to the valve open state and the route when rotating from the valve open state to the valve closed state are It is assumed that they are the same.

The butterfly valve 1 according to the present embodiment includes a valve box 2 having a valve box inner peripheral surface 2b, and the valve box inner peripheral surface 2b has a valve seat receiving portion 10. A ring-shaped valve seat member 12 serving as a valve seat of the butterfly valve 1 is attached to the valve seat receiving portion 10. The valve seat receiving portion 10 has a female threaded portion 10a, the valve seat member 12 has a male threaded portion 12e corresponding to the female threaded portion 10a, and the male threaded portion 12e is screwed into the female threaded portion 10a. As a result, a plurality of processes requiring a high degree of specialization and experience, for example, a scraping step of scraping a part of the valve box inner peripheral surface 2b, and nickel metal and stainless steel on the scraped portion of the valve box inner peripheral surface 2b. A valve based on a screwing process in which the valve seat member 12 (male threaded portion 12e) is screwed into the valve box 2 (female threaded portion 10a) instead of the welding process of sequentially welding and the cutting process of cutting the surface of stainless steel. Since the seat is formed on the valve box 2, the valve seat can be easily formed on the inner peripheral surface of the valve box 2.

Further, the valve box 2 is configured such that the inner diameter of the valve box 2 from the end portion on the fluid inflow port M side to the valve seat receiving portion 10 is larger than the outer diameter (maximum diameter) of the valve seat member 12. .. As a result, the valve seat member 12 can be easily inserted up to the valve seat receiving portion 10. Further, the valve seat receiving portion 10 has a positioning portion 10b, and the valve seat member 12 has a contact portion 12b. The abutting portion 12b abuts on the positioning portion 10b, and the movement of the positioning portion 10b to the fluid outlet N side is restricted. As a result, even if water flows in from the fluid inflow port M in the valve open state, it is possible to prevent the valve seat member 12 from moving to the fluid outflow port N side of the position determining portion 10b together with the inflowing water. Further, when the O-ring 14 is fitted into the recess formed in the abutting portion 12b, the valve seat member 12 is attached to the valve seat receiving portion 10, and the abutting portion 12b abuts on the positioning portion 10b, the O-ring is formed. 14 is deformed. As a result, even if the water flowing in from the fluid inflow port M in the valve closed state seeps between the female screw portion 10a and the male screw portion 12e, the water is surely stopped between the contact portion 12b and the positioning portion 10b. Can be done.

By the way, when a stainless steel valve seat is directly welded to a cast iron valve box 2, the valve seat may be peeled off from the valve box 2. Therefore, it is necessary to sequentially weld nickel metal and stainless steel to the cast iron valve box 2. However, if nickel metal is interposed between the cast iron valve box 2 and the stainless steel valve seat, the valve seat becomes the valve box 2. Although it does not peel off from the stainless steel, there is a problem that the price of the valve is high because it uses expensive nickel metal. Correspondingly, since the butterfly valve 1 according to the present embodiment does not use nickel metal, the price of the butterfly valve 1 can be reduced.

In the present embodiment, the valve seat member 12 is arranged on the fluid outlet N side of the rotation shaft P. That is, the valve seat receiving portion 10 to which the valve seat member 12 is attached is also arranged on the fluid outlet N side of the rotation shaft P. The valve seat receiving portion 10 may be formed on the inner peripheral surface 2b of the valve box, and may be formed on the rotation shaft P, for example. Further, in the present embodiment, the butterfly valve 1 to which the ring-shaped valve seat member 12 is attached has been described, but the valve seat member 12 may be attached to another valve, for example, a sluice valve. Further, in the present embodiment, the valve seat member 12 is made of stainless steel, but other metal members such as aluminum may be used.

Next, a modified example of the butterfly valve 1 according to the embodiment of the present invention will be described.

The valve box 2 included in the butterfly valve 1 is, for example, from a step of pouring molten iron into a sand mold corresponding to the valve box 2, a step of cooling the sand mold into which the melted iron is poured to solidify the melted iron, and a sand mold. It is obtained by sequentially executing the steps of taking out the solidified iron. That is, the valve box 2 is not composed of a plurality of members, but is composed of a single member. However, for example, when a large valve box 2 is manufactured, it is preferable that the valve box 2 is composed of a plurality of members because it is easy to transport, store, and install. Correspondingly, the valve box 2 of the butterfly valve 1 according to the present modification is composed of a plurality of members (hereinafter, referred to as “valve box members”) that can be coupled with respect to the direction of the central axis O, and each valve. A valve seat receiving portion 10 is formed on the box member.

When connecting a plurality of valve box members, the plurality of valve box members are usually joined so as to align one end of each valve box member, but it is difficult to align one end of each valve box member. In some cases. Since the valve box 2 according to this modification is composed of a plurality of valve box members and the valve seat receiving portion 10 is formed in each valve box member, each valve box member is a member of each valve box. It is coupled based on the valve seat receiving portion 10. Therefore, the valve seat receiving portion 10 of each valve box member serves as a mark when the valve box members are accurately connected. As a result, even if the valve box 2 is composed of a plurality of valve box members, each valve box member can be easily connected.

Although the present invention has been described above with reference to the above-described embodiments, the present invention is not limited to the above-described embodiments.

1 Butterfly valve 2 Valve box 2b Valve box inner peripheral surface 4 Valve body 10 Valve seat receiving part 10a Female threaded part 10b Positioning part 12 Valve seat member 12b Contact part 12c Valve seat member inner peripheral surface 12e Male threaded part

Claims (6)

A fluid inlet through which a fluid flows, a fluid passage surface through which the fluid passes, a fluid outlet through which a fluid flows in from the fluid inlet and passes through the fluid passage surface , and a fluid inlet and the fluid flow. A valve box having a valve seat receiving portion formed on the fluid passage surface between outlets, and a valve box.
A ring-shaped valve seat member attached to the valve seat receiving portion is provided.
The valve seat receiving portion is formed adjacent to the female screw portion to which the valve seat member is attached and the fluid outlet side of the female screw portion, and protrudes from the fluid passage surface with respect to the central axis of the valve box. With a part,
The valve seat member is formed on an outer peripheral surface of the valve seat member and a male screw portion corresponding to the female thread portion, a valve seat portion formed on an inner peripheral surface of the valve seat member, and a valve seat receiving portion. Has a side surface portion located on the fluid outlet side when attached,
The valve seat member is a butterfly valve characterized in that the male threaded portion is screwed into the female threaded portion and the side surface portion abuts on the protruding portion to be attached to the valve seat receiving portion . The inner peripheral surface of the valve seat member is a tapered portion, and in the valve seat member attached to the valve seat receiving portion, the inner diameter of the end portion on the fluid inflow port side is the inner diameter of the end portion on the fluid outlet side. The butterfly valve according to claim 1, wherein the butterfly valve is larger than the above. The butterfly valve according to claim 1 or 2, wherein the inner diameter of the valve box from the fluid inlet to the valve seat receiving portion is larger than the outer diameter of the valve seat member. The butterfly valve according to any one of claims 1 to 3, wherein a water blocking member is interposed between the side surface portion and the protruding portion when the side surface portion abuts on the protruding portion. .. Butterfly valve according to any one of claims 1 to 4 wherein the valve body is characterized by being composed of a plurality of parts material. A fluid inlet through which a fluid flows, a fluid passage surface through which the fluid passes, a fluid outlet through which a fluid flows in from the fluid inlet and passes through the fluid passage surface , and a fluid inlet and the fluid flow. A valve box having a valve seat receiving portion formed on the fluid passage surface between outlets and a ring-shaped valve seat member attached to the valve seat receiving portion are provided, and the valve seat receiving portion is the valve. The valve has a female threaded portion to which a seat member is attached, and a protruding portion formed adjacent to the fluid outlet side of the female threaded portion and protruding from the fluid passage surface with respect to the central axis of the valve box. The seat member is attached to the male screw portion formed on the outer peripheral surface of the valve seat member and corresponding to the female thread portion, the valve seat portion formed on the inner peripheral surface of the valve seat member, and the valve seat receiving portion. The valve seat member has a side surface portion located on the fluid outlet side at the time, and the male threaded portion is screwed into the female threaded portion, and the side surface portion abuts on the protruding portion. In the method for manufacturing a butterfly valve, which is attached to the valve seat receiving portion .
An insertion step of inserting the valve seat member into the valve box, and
A screwing step of screwing the male threaded portion into the female threaded portion, and
A method for manufacturing a butterfly valve, which comprises a contact step in which the side surface portion abuts on the protruding portion.

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