Regulating valve

Abstract

To provide an adjusting valve capable of fully opening and fully closing a channel easily at emergency and the like.SOLUTION: An adjusting valve is equipped with a valve box, a first valve seat, a first valve body, a first driving portion, a second valve seat, a second valve body, and a second driving portion. The valve body internally has a channel that has a single first common path, a first branch path and a second branch path branched off from the first common path, and a single second common path where the first branch path and the second branch path merge, and in which a fluid passes through from an inflow port of the first common path toward an outflow port of the second common path. The first valve seat is provided in the first branch path and is formed with a first valve seat port. The first valve body can open / close the first valve seat port according to the axial movement of a first valve shaft. The second valve seat is provided at a branch point from the first common path to the first branch path and the second branch path, and is formed with a second valve seat port. The second valve body rotates with a second valve shaft as a reference to open / close the second valve seat port, thereby switching a communication state of the first common path and the first branch path and the second branch path.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a control valve provided in a piping system through which a fluid such as steam flows, for adjusting the flow rate of the fluid.

Background Art

[0002] There is a globe valve or the like as an on-off valve used in a slightly open state (for example, see Patent Document 1). The globe valve adjusts the flow rate by moving the valve body up and down by turning a handle to move the valve stem up and down.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above-described control valve, due to its structure, the fluid resistance is very large, and since the full pressure of the fluid is received by the valve stem at the time of closing, the closing torque is large. Therefore, when a trouble that requires an emergency response occurs upstream or downstream of the valve, it is difficult to quickly close the valve. In this case, it is also difficult to keep the opening degree constant.

[0005] An object of the present invention is to provide a control valve that can easily fully open or fully close the flow path in an emergency or the like.

Means for Solving the Problems

[0006] The regulating valve for adjusting the flow rate of a fluid provided by the present invention includes a valve box, a first valve seat, a first valve body, a first driving part, a second valve seat, a second valve body, and a second driving part. The valve box is a flow path having a single first common passage, a first branch path and a second branch path branched from the first common passage, and a single second common passage where the first branch path and the second branch path merge, and has, inside, a flow path through which the fluid passes from the inlet of the first common passage toward the outlet of the second common passage. The first valve seat is provided in the first branch path, and a first valve seat port is formed. The first valve body can open and close the first valve seat port as the first valve shaft moves axially. The first driving part moves the first valve shaft axially. The second valve seat is provided at the branch point from the first common passage to the first branch path and the second branch path, and a second valve seat port is formed. The second valve body is a substantially spherical valve body having a switching flow path, and can switch the communication state between the first common passage and the first branch path and the second branch path by rotating about the second valve shaft to open and close the second valve seat port. The second driving part rotates the second valve shaft to switch the second valve body to a position where the flow path is fully closed, a position where the first common passage communicates with the first branch path, and a position where the first common passage communicates with the first branch path and the second branch path.

[0007] The switching flow path may have a flow path whose cross section in a direction orthogonal to the second valve shaft is T-shaped and can be connected to the first common passage and the second branch path, and a flow path extending axially of the second valve shaft from the branch point of the T-shaped flow path and connected to the first branch path.

[0008] The first valve shaft and the second valve shaft may be arranged on the same axis such that the first valve body and the second valve body are positioned therebetween.

Advantages of the Invention

[0009] According to this invention, instead of the first valve body for adjusting the flow rate, a substantially spherical second valve body having a switching flow path can be used to fully open or fully close the flow path. Therefore, even in an emergency or the like, the flow path can be easily fully opened and fully closed while maintaining the opening degree of the first valve body.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Mode for Carrying Out the Invention

[0011] A control valve which is an embodiment of the present invention will be described with reference to the drawings. Note that the configuration of the present invention is not limited to the embodiment.

[0012] FIG. 1 is a cross-sectional view of a regulating valve 1 according to an embodiment of the present invention. In the present embodiment, a globe valve is applied as the regulating valve 1.

[0013] The regulating valve 1 is arranged in a piping system of a plant (process system) such as a gas plant or a steam plant, and adjusts the flow rate of a fluid such as steam flowing through the piping system. The regulating valve 1 of the present embodiment basically adjusts the flow rate of the fluid by controlling the first valve body 42 (first valve part 4) during normal times. Also, in an emergency or the like, the flow path is fully opened or fully closed by controlling the second valve body 52 (second valve part 5).

[0014] The regulating valve 1 is composed of a valve box (body) 2, a shaft mounting part 3, a first valve part 4, a second valve part 5, a first drive part 6, a second drive part 7, etc.

[0015] Piping connection parts 8 and 9 to which piping (not shown) is connected are fixed to both ends of the valve box 2 by welding or the like. Also, a connection flange 10 is formed at the upper end of the valve box 2. A connection flange 11 formed at the lower end of the shaft mounting part 3 is fastened to the connection flange 10 by bolts 12.

[0016] In addition, in the valve box 2, a flow path 21 is formed that connects from the pipe connection part 8 via the inlet 20 and the outlet 25 to the pipe connection part 9. The fluid of the pipe connection part 8 flows into the flow path 21 from the inlet 20 and flows out from the outlet 25 to the pipe connection part 9.

[0017] The flow path 21 is composed of a first common passage 22, a first branch path 23A, a second branch path 23B, a second common passage 24, etc. Also, a first valve part 4 and a second valve part 5 are arranged in the flow path 21.

[0018] The first common passage 22 is a single flow path that communicates the inlet 20 and the second valve part 5. The first branch path 23A is a flow path that communicates the second valve part 5 and the second common passage 24 via the first valve part 4. The second branch path 23B is a flow path that communicates the second valve part 5 and the second common passage 24 without passing through the first valve part 4. The second common passage 24 is a single flow path that communicates the first branch path 23A and the second branch path 23B with the outlet 25.

[0019] The first valve part 4 is arranged on the first branch path 23A and has a first valve seat 41, a first valve body 42, and a first valve rod 45. The first valve part 4 adjusts the flow rate of the fluid in the first branch path 23A.

[0020] The first valve seat 41 is an annular valve seat formed of a metal such as stainless steel, and communicates the upstream side (the second valve part 5 side) and the downstream side (the second common passage 24 side) of the first branch path 23A via a circular first valve seat port 43.

[0021] The first valve body 42 is a ball-shaped valve body formed of a metal such as stainless steel, and is arranged to face the first valve seat port 43. Also, the first valve body 42 is displaceable between a fully closed position and a fully open position by the axial movement of the first valve rod 45. The fully closed position is the position where the first valve body 42 seats on the first valve seat 41 and closes (fully closes) the first valve seat port 43. The fully open position is the state where the first valve body 42 is separated from the first valve seat 41 and fully opens the first valve seat port 43.

[0022] The first valve rod (first valve shaft) 45 is axially mounted on the axial mounting portion 3 so as to be movable in the axial direction (the vertical direction in FIG. 1). One end of the first valve rod 45 has the upper part of the first valve body 42 fixed thereto, and the first drive portion 6 is connected to the other end. The first valve rod 45 moves axially by turning the handle 61.

[0023] The second valve portion 5 has a second valve seat 51 (51A, 51B), a second valve body 52, and a second valve shaft 55. The second valve portion 5 is disposed at the branch point from the first common passage 22 to the first branch passage 23A and the second branch passage 23B, and switches the fluid flow path. Specifically, it switches the communication state between the first common passage 22 and the first branch passage 23A and the second branch passage 23B.

[0024] The second valve seats 51A, 51B are, for example, annular valve seats made of a metal such as stainless steel or a Teflon (registered trademark) resin, and circular second valve seat openings 53A, 53B are formed. Also, the second valve seats 51A, 51B form a circular second valve seat opening 53C.

[0025] The second valve seat 51A is disposed between the first common passage 22 and the second valve body 52. The second valve seat 51B is disposed between the second valve body 52 and the second branch passage 23B. The second valve seats 51A, 51B are in contact with the second valve body 52 by the biasing force of, for example, a disc spring (not shown). That is, the second valve body 52 is always seated on the second valve seats 51A, 51B.

[0026] The second valve seat opening 53A communicates the first common passage 22 and the switching flow path 54 of the second valve body 52 when the second valve body 52 is in the states shown in FIGS. 2(A) and 2(B). The second valve seat opening 53B communicates the switching flow path 54 and the second branch passage 23B when the second valve body 52 is in the states shown in FIGS. 2(B) and 2(C). The second valve seat opening 53C communicates the switching flow path 54 and the first branch passage 23A.

[0027] The second valve body 52 is formed of a metal such as stainless steel, has a substantially spherical shape (square ball valve), and has a switching flow path 54 inside. Further, the second valve body 52 can rotate around the second valve rod 55 to open and close the second valve seat ports 53A and 53B. By the rotation of the second valve body 55, the communication state between the first common passage 22, the first branch passage 23A, and the second branch passage 23B is switched.

[0028] In the present embodiment, the second valve body 52 can be switched (rotated) to a position where the first common passage 22 communicates with the first branch passage 23A ((FIGS. 1 and 2(A)), a position where the first common passage 22 communicates with the first branch passage 23A and the second branch passage 23B (FIG. 2(B)), and a position where the flow path 21 is fully closed (FIG. 2(C)).

[0029] Note that the position where the flow path 21 is fully open is the position where the first common passage 22 communicates with the first branch passage 23A and the second branch passage 23B shown in FIG. 2(B).

[0030] As shown in FIG. 2, the switching flow path 54 has flow paths 54A and 54B. As shown in FIG. 3, the flow path 54A has a T-shaped cross section in a direction orthogonal to the second valve rod 55. FIG. 3 is a cross-sectional view taken along the line X-X of FIG. 2(A) and shows only the second valve body 52. The flow path 54A can be connected to the first common passage 22 and the second branch passage 23B.

[0031] The flow path 54B extends from the branch point of the T-shaped flow path 54A in the axial direction of the second valve shaft 55 (upward direction in FIG. 2) and is always connected to the first branch passage 23A.

[0032] Note that the shape of the switching flow path 54 is not limited to the illustrated shape as long as the communication state between the first common passage 22, the first branch passage 23A, and the second branch passage 23B can be switched.

[0033] The second valve rod (second valve shaft) 55 is rotatably supported by the valve box 2 while being inserted from the bottom surface of the valve box 2. The second valve rod 55 is arranged on the same axis as the first valve rod 45. Further, a second valve body 52 is fixed to one end of the second valve rod 55, and a handle 71 of the second drive unit 7 is connected to the other end. The second valve rod 55 rotates by turning the handle 71.

[0034] The first drive unit 6 is arranged above the valve box 2 and manually moves the first valve rod 45 in the axial direction. The first drive unit 6 includes a handle 61, a yoke sleeve 62, etc.

[0035] The handle 61 is fitted into the upper part of the yoke sleeve 62. A female thread groove (not shown) that engages with a male thread groove (not shown) formed on the outer periphery of the first valve rod 45 is formed in the yoke sleeve 62.

[0036] Thereby, by turning the handle 61, the first valve rod 45 moves in the axial direction via the yoke sleeve 62.

[0037] The second drive unit 7 is arranged below the valve box 2 and manually rotates the second valve rod 55. That is, the second drive unit 7 rotates the second valve body 52 to each of the above-described positions. The second drive unit 7 includes a handle 71, etc. The handle 71 is fixed to the end of the second valve rod 55 by a bolt 72.

[0038] Thereby, by turning the handle 71, the second valve rod 55 rotates in the same direction as the handle 71.

[0039] Next, an operation example of the regulating valve 1 will be described.

[0040] Normally, basically, the flow rate of the fluid in the flow path 21 is adjusted by controlling the position (opening degree) of the first valve body 42.

[0041] Specifically, the second valve body 52 is fixed at a position where the first common passage 22 and the first branch passage 23A shown in FIG. 2(A) communicate with each other. As a result, the fluid flows from the first common passage 22 through the first branch passage 23A and into the second common passage 24. Then, by changing the position of the first valve body 45 as needed, the flow rate of the fluid is adjusted.

[0042] On the other hand, in an emergency or the like, the flow path 21 is fully opened or fully closed by controlling the position of the second valve body 52.

[0043] Specifically, the second valve body 52 is changed to a position where the flow path 21 shown in FIG. 2(B) is fully opened or a position where the flow path 21 shown in FIG. 2(C) is fully closed according to the situation in an emergency or the like. That is, when the first common passage 22 communicates with the first branch passage 23A and the second branch passage 23B, the flow path 21 is fully opened. Also, when the second valve seat port 53A is closed, the flow path 21 is fully closed.

[0044] Since the second valve body 52 is a ball valve body, it has excellent airtightness. Also, since the second valve rod 55 does not move in the axial direction, the pressure of the fluid received when fully closed is smaller than that of the first valve rod 45, so it is easier to rotate compared to the first valve rod 45.

[0045] In an emergency or the like, the first valve body 45 may remain in its current position (opening degree) without being moved. That is, even if the position of the first valve body 45 is not adjusted, the flow path 21 can be fully closed (fully opened).

[0046] As described above, in the embodiment of the present invention, instead of the first valve body for adjusting the flow rate, a substantially spherical second valve body having a switching flow path is used to fully open or fully close the flow path. Therefore, even when the opening degree of the first valve body is maintained in an emergency or the like, the flow path can be easily fully opened or fully closed.

[0047] In the above-described embodiment, a spherical valve body (globe valve) is used as the first valve body, but the present invention is not particularly limited thereto. As long as it is an on-off valve that opens and closes a valve seat with a valve body by moving a valve shaft up and down, a gate valve, a needle valve, a plug valve, or the like may be applied to the present invention.

[0048] In the above-described embodiment, the first drive unit and the second drive unit are configured to be manually driven, but the present invention is not particularly limited thereto. A drive unit such as a motor drive or an air drive may also be used.

[0049] In the above-described embodiment, the second valve portion is disposed below the first valve portion. However, the present invention is not particularly limited thereto as long as the second valve portion is located at the branch point of the first branch passage and the second branch passage. Further, the shape of the flow path is not limited to the above-described embodiment.

[0050] In the above-described embodiment, the regulating valve in a state where the first drive unit is located above as shown in FIG. 1 has been described. However, the arrangement direction of the regulating valve is not particularly limited thereto.

Industrial Applicability

[0051] The present invention can be used in fields such as regulating the flow rate of fluids such as steam flowing through a piping system of a plant (process system) such as a steam plant.

Explanation of Reference Numerals

[0052] 1 Regulating valve 2 Valve box 4 First valve portion 5 Second valve portion 6 First drive unit 7 Second drive unit 21 Flow path 22 First common passage 23A First common passage 23B Second common passage 24 Second common passage 41 First valve seat 42 First valve body 43 First valve seat port 45 First valve rod (first valve shaft) 51(51A, 51B) Second valve seat 52 Second valve body 53(53A~53C) Second valve seat port 54 Switching flow path 55 Second valve rod (second valve shaft)

Claims

1. A control valve for adjusting the flow rate of a fluid, comprising: a valve box having a flow path including a single first common passage, a first branch path and a second branch path branching from the first common passage, and a single second common passage into which the first branch path and the second branch path merge, the valve box having inside thereof a flow path through which the fluid passes from an inlet of the first common passage toward an outlet of the second common passage; a first valve seat provided in the first branch path and having a first valve seat port formed therein; a first valve body capable of opening and closing the first valve seat port as the first valve shaft moves axially; a first driving portion for axially moving the first valve shaft; a second valve seat provided at a branch point from the first common passage to the first branch path and the second branch path and having a second valve seat port formed therein; a substantially spherical valve body having a switching flow path, the second valve body being capable of switching the communication state between the first common passage and the first branch path and the second branch path by rotating about a second valve shaft to open and close the second valve seat port; a second driving portion for rotating the second valve shaft to switch the second valve body to a position where the flow path is fully closed, a position where the first common passage and the first branch path communicate with each other, and a position where the first common passage and the first branch path and the second branch path communicate with each other; A control valve characterized by comprising the above components.

2. The switching flow path has a flow path whose cross section in a direction orthogonal to the second valve shaft is T-shaped and which can be connected to the first common passage and the second branch path, and a flow path extending axially of the second valve shaft from a branch point of the T-shaped flow path and connected to the first branch path. The control valve according to Claim 1.

3. The first valve shaft and the second valve shaft are arranged on the same axis such that the first valve body and the second valve body are positioned therebetween. The control valve according to Claim 1 or Claim 2.

Images