JP2018119576A - Valve, valve seat member, valve box, and method of mounting valve seat member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a valve which allows easily forming a valve seat on an inner peripheral surface of a valve box.SOLUTION: A butterfly valve 1 includes a valve box 2 having a valve box inner peripheral surface 2b, and a ring-like valve seat member 12. The valve box inner peripheral surface 2b has a valve seat reception part 10. The valve seat reception part 10 has a female screw part 10a. The valve seat member 12 has a male screw part 12e corresponding to the female screw part 10a. The male screw part 12e is screwed into the female screw part 10a, so that the valve seat member 12 is mounted on the valve seat reception part 10.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a valve, a valve seat member, a valve box, and a mounting method of the valve seat member.

  Conventionally, a cylindrical 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 stem and whose valve body rotates about the valve stem 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 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 cutting a part of the inner peripheral surface of the valve box, sequentially welding nickel metal and stainless steel to the cut parts, and cutting the surface of the stainless steel. The

JP 2011-220470 A

  However, in order for the valve body to be seated on the valve seat and to reliably dam the fluid flowing through the pipeline, the cutting process applied to the surface of the stainless steel must be made precisely, requiring high expertise and experience. become. In addition, in order to form a stainless steel valve seat on the inner peripheral surface of a cast iron valve box, multiple steps are required from the process of cutting the valve box to the process of cutting the stainless steel surface. In order to form the valve seat in the valve box, a long time is required. 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 valve, a valve seat member, a valve box, and a mounting method for the valve seat member, which can easily form a valve seat on the inner peripheral surface of the valve box.

  To achieve the above object, a valve according to the present invention includes a valve box having a fluid passage surface through which a fluid passes, a female screw portion formed on the fluid passage surface, and a ring having a male screw portion corresponding to the female screw portion. The male screw part is formed on the outer peripheral surface of the valve seat member and is screwed into the female screw part.

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

It is the schematic of the butterfly valve which concerns on embodiment of this invention, Comprising: FIG. 1 (A) is a front view of a butterfly valve, FIG.1 (B) is a side view of a butterfly valve. 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. FIG. 4 is an enlarged view of a region C in FIG. 3. It is a perspective view of the valve seat member in FIG. It is sectional drawing which follows the BB line of the butterfly valve of FIG.

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

  FIG. 1 is a schematic view of a butterfly valve 1 according to an embodiment of the present invention. FIG. 1 (A) is a front view of the butterfly valve 1, and FIG. 1 (B) is a side view of the butterfly valve 1. It is.

  The butterfly valve 1 in FIG. 1 includes a valve box 2 made of cast iron, a substantially disc-shaped valve body 4 housed in the valve box 2, blocking members 8a and 8b, and a valve seat member 12 made of stainless steel. The valve box 2 has a cylindrical shape having a central axis O, and is arranged in the valve box outer peripheral surface 2a along the circumferential direction and in the valve box through which a fluid passes and is disposed closer to the central axis O than the valve box outer peripheral surface 2a. And a peripheral surface 2b (fluid passage surface). The inner diameter of the valve box 2 may vary along the central axis O. Each of the both end portions 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, the 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 and nuts or the like. In the present embodiment, it is assumed that the butterfly valve 1 is connected to a water pipe, and 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) through which a later-described valve shaft 3 is inserted. The valve shaft 3 penetrates the valve body 4 through 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 valve box outer peripheral surface 2a 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 8 a and 8 b, and the valve body 4 rotates around the valve shaft 3.

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

  The valve box 2 in FIG. 2 includes 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 through the insertion holes 7a and 7b. That is, the butterfly valve 1 is assembled by sequentially inserting a later-described 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 line AA of the butterfly valve 1 of FIG.

  The butterfly valve 1 in FIG. 3 includes a rotation shaft P that is orthogonal to the central axis O and rotates when the valve body 4 rotates, and includes a valve seat member 12 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 a region C in FIG. 3 and is a view for explaining the periphery of the valve seat receiving portion 10.

  The valve seat receiving part 10 of FIG. 4 protrudes from the internal threaded part 10a for attaching the valve seat member 12 to the central axis O side from the valve box inner peripheral surface 2b, and determines the position where the valve seat member 12 is attached. A position determining unit 10b. The valve seat member 12 of the present embodiment has a ring shape, has a valve seat central axis Q, and is positioned along the circumferential direction of the valve seat member 12 more than the valve seat member outer peripheral surface 12a and the valve seat member outer peripheral surface 12a. It has a valve seat member inner peripheral surface 12c disposed on the valve seat central axis Q side, and a contact portion 12b that contacts the position determining portion 10b when the valve seat member 12 is attached to the valve seat receiving portion 10. The valve seat member outer peripheral surface 12a is formed with a male screw portion 12e corresponding to the female screw portion 10a (FIG. 5). A concave portion is formed in one of the contact portion 12b and the position determining portion 10b. In the present embodiment, it is assumed that the concave portion is formed in the contact portion 12b. The O-ring 14 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 the valve seat receiving portion 10. When the contact portion 12b contacts the position determining 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 on the fluid inlet M side to the valve seat receiving part 10 is larger than the outer diameter (maximum diameter) of the valve seat member 12. Has been. Therefore, in order to attach the valve seat member 12 to the valve seat receiving portion 10, first, the valve seat member 12 is inserted into the valve box 2 from the fluid inlet M so that the central axis O and the central axis Q of the valve seat overlap. Then, the male screw portion 12e is inserted until it contacts the female screw portion 10a. Next, the male screw portion 12e is screwed into the female screw portion 10a until the abutting portion 12b comes into contact with the position determining portion 10b. When the valve seat member 12 is screwed to the valve seat member 10 and the contact portion 12b contacts the position determining portion 10b, the attachment of the valve seat member 12 to the valve seat receiving portion 10 is completed (attachment of the valve seat member). Method).

  The valve seat member inner peripheral surface 12c has, at least in part, a tapered portion 12d that is inclined with respect to the central axis O so that the diameter of the valve seat member 12 increases 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 inlet M is blocked by the valve body 4. The outer edge portion of the valve body 4 may be subjected to rubber lining processing, or may be subjected to metal processing using stainless steel metal, aluminum, or the like.

  6 is a cross-sectional view taken along 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 from the state where the water flowing in from the fluid inlet M does not flow out of the fluid outlet N (hereinafter referred to as “valve closed state”). The valve member 3 rotates or opens around the valve shaft 3 in a state where the water flowing in from the fluid inlet M flows out from the fluid outlet N without contacting the seat member 12 (hereinafter referred to as “valve open state”). The valve shaft 3 is pivoted from the valve state to the closed state. In the present embodiment, the route through which the valve element 4 passes when turning from the closed state to the open state and the route when turning from the open state to the closed state are as follows: 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 part 10 has an internal thread part 10a, the valve seat member 12 has an external thread part 12e corresponding to the internal thread part 10a, and the external thread part 12e is screwed into the internal thread part 10a. Accordingly, a plurality of processes requiring high expertise and experience, for example, a scraping process for scraping a part of the inner peripheral surface 2b of the valve box, and nickel metal and stainless steel on the shaved part of the inner peripheral surface 2b of the valve box. The valve is based on a welding process of sequentially welding and a screwing process of screwing the valve seat member 12 (male thread part 12e) to the valve box 2 (female thread part 10a) instead of the cutting process of cutting the surface of the stainless steel. Since the seat is formed in 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 on the fluid inlet M side to the valve seat receiving part 10 is larger than the outer diameter (maximum diameter) of the valve seat member 12. . Thereby, the valve seat member 12 can be easily inserted to the valve seat receiving part 10. Further, the valve seat receiving portion 10 has a position determining portion 10b, and the valve seat member 12 has a contact portion 12b. The contact portion 12b contacts the position determining portion 10b, and movement of the position determining portion 10b toward the fluid outlet N is restricted. Thereby, even if water flows in from the fluid inlet M in the valve open state, the valve seat member 12 can be prevented from moving to the fluid outlet N side of the position determining unit 10b together with the water that has flowed in. Further, when the O-ring 14 is fitted in the recess formed in the contact portion 12b, the valve seat member 12 is attached to the valve seat receiving portion 10, and the contact portion 12b contacts the position determining portion 10b, the O-ring 14 is deformed. Thereby, even if the water flowing in from the fluid inflow port M in the valve-closed state infiltrates between the female screw portion 10a and the male screw portion 12e, the water is reliably stopped between the contact portion 12b and the position determining portion 10b. Can do.

  By the way, if a valve seat made of stainless steel is directly welded to the valve box 2 made of cast iron, the valve seat may peel from the valve box 2 in some cases. Therefore, it is necessary to weld nickel metal and stainless steel sequentially to the cast iron valve box 2, but when nickel metal is interposed between the cast iron valve box 2 and the stainless steel valve seat, the valve seat is the valve box 2. However, since expensive nickel metal is used, there is a problem that the price of the valve is high. 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 disposed 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 part 10 should just be formed in the valve box internal peripheral surface 2b, for example, may be formed on the rotating shaft P. FIG. In the present embodiment, the butterfly valve 1 to which the ring-shaped valve seat member 12 is attached has been described. However, the valve seat member 12 may be attached to another valve, for example, a gate valve. Furthermore, 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 provided in the butterfly valve 1 includes, for example, 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 molten iron has been poured, and solidifying the molten iron, and a sand mold It is obtained by sequentially executing the step 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 the large valve box 2 is manufactured, the valve box 2 is preferably 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 in the direction of the central axis O, and each valve. A valve seat receiving portion 10 is formed on the box member.

  When combining a plurality of valve box members, the plurality of valve box members are usually combined so that one end of each valve box member is aligned, but it is difficult to align one end of each valve box member. There is a case. Since the valve box 2 according to the present modification is composed of a plurality of valve box members, and each valve box member is formed with a valve seat receiving portion 10, each valve box member is a member of each valve box member. The valve seat receiving part 10 is coupled. Therefore, the valve seat receiving portion 10 of each valve box member serves as a mark for accurately connecting the valve box members. Thereby, even if the valve box 2 is comprised from the member for several valve boxes, each member for valve boxes can be couple | bonded easily.

  As described above, the present invention has been described using the above-described embodiment, but the present invention is not limited to the above-described embodiment.

DESCRIPTION OF SYMBOLS 1 Butterfly valve 2 Valve box 2b Valve box inner peripheral surface 4 Valve body 10 Valve seat receiving part 10a Female thread part 10b Position determination part 12 Valve seat member 12b Contact part 12c Valve seat member inner peripheral surface 12e Male thread part

Claims (8)

A valve box having a fluid passage surface through which fluid passes;
An internal thread formed on the fluid passage surface;
A ring-shaped valve seat member having a male screw portion corresponding to the female screw portion,
The male screw part is formed on an outer peripheral surface of the valve seat member, and is screwed into the female screw part.   The valve according to claim 1, wherein the valve box includes a plurality of valve box members.   The valve according to claim 1 or 2, wherein the valve is a butterfly valve.   A valve seat member that is a ring-shaped valve seat member that is screwed into a valve box in which a female screw portion is formed, wherein a male screw portion that is screwed into the female screw portion is formed.   The valve seat member according to claim 4, wherein the male screw portion is formed on an outer peripheral surface of the valve seat member.   A valve box in which a ring-shaped valve seat member formed with a male screw part is screwed, and a female screw part into which the male screw part is screwed is formed.   The valve box according to claim 6, wherein the female screw portion is formed on an inner peripheral surface of the valve box. In the attachment method of the valve seat member for attaching the valve seat member provided with the female screw portion to the valve box provided with the male screw portion,
Inserting the valve seat member into the valve box;
And a step of screwing a male screw portion formed on the valve seat member with a female screw portion formed on the valve box.

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