Control valve

Abstract

To provide a regulating valve capable of facilitating maintenance and replacement by simply attaching and detaching a seat ring, securing a flow rate of fluid when regulating the flow rate from a minute opening to full opening, and preventing deformation and breakage of a seat retainer by sufficiently securing strength of the seat retainer.SOLUTION: The body 10 is provided with the primary side opening part 21 and the secondary side opening part 22, the cylindrical side peripheral wall part 30 of the seat retainer 13 is provided with the plurality of opening hole parts 31 through which the fluid can pass so as to be adjacent to each other in the circumferential direction, at least one of these opening hole parts is an opening hole part having a vertically asymmetric shape provided with a larger opening area on the seat ring 11 side than on the bonnet 14 side, and the seat retainer is disposed such that the opening hole part having the vertically asymmetric shape among the opening hole parts faces the secondary side opening part of the body.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a regulator valve for regulating and controlling the flow rate of a fluid. [Background technology]

[0002] This type of control valve is designed to adjust the flow rate of fluid by moving a plug (stem) back and forth relative to a seat ring attached inside the body, thereby changing the flow path area formed at the opening between the seat ring and the plug head.

[0003] Among these, globe valve-type control valves in particular are known to be capable of precise flow rate adjustment by adjusting the position of the plug relative to the seat ring, and are capable of flowing large amounts of fluid while precisely controlling the fluid flow rate, pressure, etc. In recent years, as with other types of valves, it has become desirable to be able to use control valves, including globe valve-type control valves, for long periods of time by replacing internal parts from the perspective of MRO (Maintenance Repair and Operations). For example, when the seat ring on the valve seat side deteriorates due to repeated flow control, it is desirable to be able to easily detach and replace this seat ring for maintenance.

[0004] An example of such a globe valve is the regulating valve disclosed in Patent Document 1. In this regulating valve, the seat ring is removably sandwiched between an opening in the body on the plug (stem) mounting side of the body and a cage serving as a seat retainer. This mounting structure allows the seat ring to be removed by detaching the cage when the seat ring becomes worn and requires repair, allowing for maintenance or replacement of the seat ring.

[0005] In this globe valve, two communicating holes are provided in the outer cylinder of a cylindrical cage, facing each other, and these two communicating holes are formed in a substantially identical rectangular shape when viewed from the front. Two substantially rectangular pillars are provided between the communicating holes, facing each other and parallel to the central axis of the cage. The cage is pressed from the bonnet side to press the seat ring in the installation direction, and when pressed, the cage is supported by the two pillars. The pillars are formed thinner in the vertical direction than the communicating holes, so that the communicating holes are larger than the pillars, ensuring the size of the flow paths. With this configuration, in the circumferential direction of the cage where the pillars are formed, the area of ​​the parts where the pillars are formed is smaller than the opening area of ​​the regions where the communicating holes are formed, and conversely, the cross-sectional area of ​​the parts where the pillars are formed in a direction perpendicular to the central axis of the cage is smaller than the cross-sectional area of ​​the regions where the communicating holes are formed.

[0006] On the other hand, the valve of Patent Document 2 has a seat ring attached between the primary flow path and the secondary flow path inside the body, and a cylindrical cage for adjusting the flow rate is provided adjacent to the seat ring in the vertical direction. The cylindrical portion of the cage has a plurality of through-holes for adjusting the flow rate, which are formed in a roughly triangular shape on the circumferential surface, and each roughly triangular through-hole is oriented so that the opening area on the seat ring side is larger. The provision of these through-holes creates pillars between the through-holes, which support the cylindrical portion of the cage.

[0007] A cylindrical plug is attached to the inner periphery of the cage so that it can move up and down, and the flow rate is adjusted by changing the size of the opening between the tip of the plug and the through-hole in the cage as the plug moves up and down. When the valve is closed, the tip of the plug abuts against the seat ring, and the plug and seat ring form a seal. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] U.S. Patent Registration No. 3,504,888 [Patent Document 2] U.S. Patent Publication No. 2017-102076 Summary of the Invention [Problem to be solved by the invention]

[0009] In the control valve of Patent Document 1, after adjusting the flow rate by the gap between the plug and the seat ring when the valve is open, in order to maintain the flow rate of the fluid passing through the cage (seat retainer) and ensure the Cv value, it is necessary to make the communicating hole of the cage somewhat large. In particular, to ensure the flow rate on the seat ring side where the plug of the communicating hole contacts and separates, it is necessary to make the seat ring side of the communicating hole significantly wider. In this case, the overall opening area of ​​the approximately rectangular communicating hole becomes larger, and therefore the pillar portions between the communicating holes become thinner and their cross-sectional areas become smaller.

[0010] Therefore, when the seat ring is installed, a large force is applied to each pillar from the hood. Moreover, because the pillars are provided in only two locations around the circumference of the cage (the minimum necessary), the force applied to each pillar is greater than when pillars are provided in three locations, making it difficult to distribute the stress. Furthermore, because the pillars are formed at 180° intervals with respect to the cage, the strength is significantly reduced near the through-holes located 90° apart from these pillars. In addition, excessive stress tends to concentrate near the four corners of the rectangular through-holes, further reducing the strength.

[0011] In this way, if the communicating holes are rectangular and made larger to ensure sufficient flow rate when the valve is open, from slightly open to fully open, the pillars become smaller, which makes it impossible to ensure sufficient strength in the compressive direction of the cage after the seat ring is installed. In this case, after the seat ring is installed, uneven stress acts on the pillars of the seat retainer over a long period of time, which can reduce the durability of the cage and lead to deformation or breakage.

[0012] For this reason, in the case of a control valve equipped with a cage (seat retainer) of the type described in Patent Document 1, it is difficult to ensure both the strength of the seat retainer by the pillar portion and the flow rate of the fluid passing through the communicating hole, making it difficult to satisfy both of these requirements.

[0013] On the other hand, in the valve of Patent Document 2, the cage is provided to adjust the flow rate by changing the opening area of ​​the through-hole through the up-and-down movement of the plug, but there is no mention of using this cage to secure the seat ring to the body. As such, unlike the structure of Patent Document 1, which retains the seat ring by applying force from the bonnet to press the seat ring against the valve seat retainer, this valve requires the seat ring to be attached to the body by another attachment method, such as threading. In this case, the seat ring's detachability is significantly reduced compared to the seat ring attachment structure of Patent Document 1, and there is a risk that the seat ring will become fixed to the body after long-term use, making maintenance and replacement difficult and even requiring the entire body to be replaced. In addition, when the seat ring is secured by threading, high machining precision is required for the threaded portion to be attached to the body in the desired position.

[0014] The cage's multiple, approximately triangular through-holes are all oriented in a direction that, along the central axis of the cylindrical portion, provides a wider opening on the seat ring side. Therefore, the column sections between these through-holes are tapered toward the seat ring side, and their cross-sectional areas are also smaller toward the seat ring side. Therefore, when a force is applied along the cage's central axis, stress tends to act locally on the seat ring side of the column sections, making it difficult to ensure the cage's overall strength. This makes it difficult to ensure consistent circumferential strength of the cylindrical portion along the central axis.

[0015] In contrast to these, the through-hole of the cage is set to a predetermined shape and size in order to adjust the flow rate by changing the degree of opening depending on its position relative to the tip of the plug, and therefore it is not possible to make the through-hole smaller and thicken the column in order to improve the strength of the column. Therefore, it is difficult to improve the overall strength of the cage while maintaining a predetermined flow rate regulation and ensuring a high flow rate.

[0016] The present invention was developed to solve the above-mentioned problems, and its purpose is to provide a control valve in which the seat ring can be easily attached and detached to facilitate maintenance and replacement, the flow rate of fluid can be ensured when adjusting the flow rate from a small opening to a full opening, and the strength of the seat retainer can be sufficiently ensured to prevent deformation or damage. [Means for solving the problem]

[0017] In order to achieve the above object, the invention of claim 1 is a control valve in which an annular seat ring is disposed in a valve seat retaining portion formed in a body, and this seat ring is fixed by being pressed from above against the valve seat retaining portion by a bonnet via a cylindrical seat retainer, and a plug having a valve body portion at its tip is provided so as to be able to advance and retreat relative to the seat ring, and the degree of contact and separation between the valve body portion and the seat ring can be adjusted to control the fluid, and the body is provided with a primary side opening through which the fluid flows in and a secondary side opening through which the fluid flows out, and a cylindrical side wall portion of the seat retainer is provided with a plurality of opening holes that are adjacent to each other in the circumferential direction, and at least one of these opening holes is an opening hole with a vertically asymmetrical shape that has a larger opening area on the seat ring side than on the bonnet side, and the seat retainer is arranged so that one of the opening holes with a vertically asymmetrical shape faces the secondary side opening of the body.

[0018] The invention according to claim 2 is a regulator valve in which the seat retainer is provided so that adjacent open hole portions have different shapes from each other in the circumferential direction.

[0019] The invention according to claim 3 is a regulating valve in which at least the opening hole portion having a vertically asymmetrical shape is formed in a generally triangular shape when viewed from the front.

[0020] The invention according to claim 4 is a control valve in which the opening hole portion having an asymmetrical shape in the up-down direction is disposed inside the secondary opening portion in the direction of fluid flow.

[0021] The invention according to claim 5 is a flow-under type control valve in which the body is configured so that fluid flowing in from the primary side opening passes through the seat ring from below to above and flows out from the secondary side opening.

[0022] The invention of claim 6 is a control valve in which an annular seat ring is disposed in a valve seat retaining portion formed in a body, and this seat ring is pressed against and fixed to the valve seat retaining portion by the bonnet via a cylindrical seat retainer, and a plug with a valve body portion at its tip is disposed so as to be able to move forward and backward relative to the seat ring, and fluid control is possible by adjusting the degree of contact and separation between the valve body portion and the seat ring, and the seat retainer is composed of a bonnet-side annular portion disposed on the bonnet side, a seat ring-side annular portion disposed on the seat ring side, and multiple pillars connecting these annular portions, and is generally cylindrical in shape, and opening holes through which fluid can pass are formed between adjacent pillars, and each pillar has a generally constant width from the bonnet-side annular portion to the seat ring-side annular portion, and is formed at an angle to the axial direction of the generally cylindrical seat retainer.

[0023] The invention according to claim 7 is a regulator valve in which the pillar-shaped portions are provided such that adjacent pillar-shaped portions in the circumferential direction of the seat retainer are inclined in opposite directions relative to the axial direction of the seat retainer. [Effects of the Invention]

[0024] According to the invention of claim 1, the seat ring is pressed and fixed by the seat retainer, and the fluid is controlled by adjusting the degree of contact and separation of the valve body portion at the tip of the plug relative to the seat ring. This allows the seat ring to be easily attached and detached by removing the seat retainer, facilitating maintenance and replacement. The cylindrical side wall of the seat retainer is provided with multiple adjacent openings in the circumferential direction, through which fluid can pass, and at least one of these openings has a larger opening area on the seat ring side than on the bonnet side. This ensures a large opening in the area where the fluid flows most, without requiring the overall openings to be excessively large. Therefore, when the valve is open, the opening area on the contact and separation side between the plug and seat ring, where the fluid flows most easily, can be increased without obstructing the flow of fluid to the secondary side, particularly at the initial small opening angle during valve opening, thereby ensuring a sufficient flow rate. Furthermore, since the opening hole portion, which is asymmetrical in shape from top to bottom, is positioned opposite the secondary opening of the body, the fluid that passes through the seat retainer through this opening hole portion can flow in a straight line toward the secondary opening, ensuring a flow rate after flow rate adjustment from a small opening to a fully opened state. In addition to the above, the seat retainer has sufficient strength throughout, and deformation or damage to the seat retainer can be prevented without making the entire opening excessively large, allowing the seat retainer to firmly hold the seat ring for a long period of time. In this way, it is possible to ensure both the strength of the seat retainer and the flow rate of fluid passing through the seat retainer.

[0025] According to the invention of claim 2, the seat retainer is arranged so that adjacent opening hole portions have different shapes in the circumferential direction. Therefore, the opening hole portions having asymmetric shapes in the up and down directions ensure sufficient flow rate at the initial small opening angle when the valve is opened, and by providing the opening hole portions in various shapes, the strength of the side peripheral wall portion can be ensured and the load applied from the bonnet side to the seat ring side can be distributed to prevent deformation or damage to the seat ring.

[0026] According to the invention of claim 3, at least the opening hole portions having an asymmetrical shape in the upper and lower directions are formed into a roughly triangular shape when viewed from the front, thereby ensuring the largest opening area on the side where fluid flows most easily, particularly in the initial stage when the valve is opened, thereby further improving the ease of fluid flow until the valve is fully open.

[0027] According to the invention of claim 4, the opening hole portion having an asymmetrical shape in the vertical direction is positioned inside the secondary opening in the direction of fluid flow, thereby allowing the fluid flowing from the opening hole portion having an asymmetrical shape in the vertical direction to flow in a straightened state without being obstructed, thereby improving the ease of flow.

[0028] According to the invention of claim 5, a flow-under type is adopted in which the fluid that flows in from the primary opening passes through the seat ring from bottom to top and flows out from the secondary opening, which is advantageous in maintaining the strength of the seat retainer while ensuring a high flow rate.

[0029] According to the invention of claim 6, the seat ring is pressed and fixed by the seat retainer, and the fluid is controlled by adjusting the degree to which the valve body at the tip of the plug approaches and separates from this seat ring. This allows for minute flow rate adjustments to be performed with high precision, and the seat ring can be easily detached by removing the seat retainer, facilitating maintenance and replacement. The seat retainer is generally cylindrical and includes a bonnet-side annular portion, a seat ring-side annular portion, and a plurality of pillars. The pillars have openings between adjacent pillars, allowing fluid to pass through. By adjusting the shape, width, and cross-sectional area of ​​the pillars, the strength of the seat retainer and the size of the openings can be adjusted. In particular, by providing the pillars with a generally constant width from the bonnet-side annular portion to the seat ring-side annular portion, the load applied from the bonnet side to the pillars in the vertical direction can be uniformly distributed, avoiding stress concentration and reducing damage and deformation. In addition, by forming the pillars at an angle with respect to the axial direction of the cylindrical seat retainer, the load from the bonnet side is transmitted obliquely with respect to the axial direction of the seat retainer, allowing the load to be distributed over a longer distance than when the pillars are provided parallel to the axial direction. In this way, it is possible to ensure both the strength of the seat retainer and the flow rate when fluid passes through the seat retainer, and further, by keeping the size, such as the shape and width of the columnar portion, and the cross-sectional area as small as possible to ensure strength, the opening area of ​​the opening hole portion can be increased to improve ease of flow.

[0030] According to the invention of claim 7, the columnar portions support each other, which is a shape that is more advantageous for resisting forces applied in the vertical direction. [Brief explanation of the drawings]

[0031] [Figure 1] 1 is a schematic longitudinal sectional view showing an embodiment of a regulator valve according to the present invention. [Figure 2] FIG. 2 is a partially enlarged cross-sectional view showing the vicinity of the valve main body of FIG. 1. [Figure 3] FIG. [Figure 4] 3 is a cross-sectional view taken along the line AA in FIG. 2. [Figure 5] FIG. 10 is a schematic diagram showing the relationship between a seat retainer and a secondary-side opening. DETAILED DESCRIPTION OF THE INVENTION

[0032] An embodiment of a control valve according to the present invention will be described in detail below with reference to the drawings. Fig. 1 is a schematic longitudinal cross-sectional view showing an embodiment of a control valve according to the present invention, Fig. 2 is a partially enlarged cross-sectional view showing the vicinity of the valve main body in Fig. 1, and Fig. 4 is a cross-sectional view taken along line AA in Fig. 2.

[0033] 1 to 4, the control valve (hereinafter referred to as valve body 1) in the embodiment of the present invention has a globe valve type structure and is provided with a diameter size of, for example, 1 / 2 to 4 inches, and uses water, steam, air, and various other fluids as its working fluids. When the valve is open, these fluids can flow while regulating the flow rate, while when the valve is closed, leakage of these fluids can be prevented.

[0034] The valve body 1 comprises a valve body portion 2 and an actuator 3, of which the valve body portion 2 has a body 10, a seat ring 11, a gasket 12, a seat retainer 13, a bonnet 14, a plug guide 15, and a plug (stem) 16.

[0035] The body 10 of the valve main body 2 is formed from a metal material such as carbon steel casting, and is provided with an inlet 10a and an outlet 10b on either side. A substantially cylindrical mounting recess 10c is bored out in the substantially vertical direction between the inlet 10a and the outlet 10b, and the inlet 10a and the outlet 10b on either side are connected through this mounting recess 10c. An opening 10d is formed on the upper side of the mounting recess 10c, and a groove-shaped valve seat holder 17 is formed on the lower side of the mounting recess 10c, and an annular seat ring 11 is provided to be able to be placed against this annular valve seat holder 17.

[0036] In the valve body 1, a seat ring 11 is arranged in the valve seat holding portion 17 of the body 10, and this seat ring 11 is pressed from above against the valve seat holding portion 17 by a bonnet 14 via a seat retainer 13 to be fixed, and a plug 16 is provided so as to be able to move forward and backward relative to the seat ring 11.

[0037] The plug 16 is formed into an elongated shape from a metal material such as a stainless steel alloy, and includes, in the axial direction, a small-diameter portion 19 that is attached to the drive side of the actuator 3, and a large-diameter portion 20 that is larger in diameter than the small-diameter portion 19 and is provided on the seat ring 11 side. The plug 16 is inserted into a plug insertion hole 40, which will be described later, with the large-diameter portion 20 inserted and guided by the inner periphery of the plug guide 15, and is attached to the bonnet 14 in a state in which it can advance and retreat relative to the seat ring 11.

[0038] A valve body portion 18 is provided at the tip of the plug 16, and when the plug 16 is moved back and forth, the outer periphery of the valve body portion 18 can approach or separate from the seat ring 11. The contact (abutment) of this valve body portion 18 with the seat ring 11 closes the flow path, or by adjusting the degree of separation when the valve body portion 18 approaches or separates from the seat ring 11, the flow rate when the valve is open can be controlled.

[0039] A flow rate adjusting portion 18a having a generally truncated cone shape that gradually decreases in diameter as it extends downward is provided on the lower side of the valve body portion 18, and a generally conical inclined surface 18b that becomes sharper toward the center is provided on the bottom side of this flow rate adjusting portion 18a. When the valve is open, the fluid flows through this inclined surface 18b, making it possible to adjust the flow rate while maintaining a high Cv value. On the other hand, a tapered portion 18c having approximately the same angle as a tapered surface 25 (described later) formed on the seat ring 11 is provided on the upper portion of the flow rate adjustment portion 18a, and this tapered portion 18c is arranged to be able to abut and seal against the tapered surface 25 when the valve is closed.

[0040] The regulating valve is capable of adjusting the flow rate of the fluid by moving the plug 16 back and forth using the actuator 3 . In this case, when the tapered portion 18c of the valve body portion 18 and the tapered surface 25 of the seat ring 11 come into contact (abut), the valve is closed, providing high sealing performance and reliably preventing fluid leakage. On the other hand, when the plug 16 is raised from the valve closed state of the valve body 18, the tapered portion 18c moves away from the tapered surface 25, bringing the valve into an open state. In this state, the plug 16 is moved back and forth to finely change the size of the gap between the flow rate adjustment portion 18a of the valve body 18 and the tapered surface 25 of the seat ring 11, thereby enabling the flow rate to be adjusted from a small flow rate to a large flow rate while finely adjusting the valve opening.

[0041] The actuator 3 is attached to the end of the plug 16 opposite the valve body portion 18, and applies a driving force to operate the plug 16. The actuator 3 moves the plug 16 up and down to close the valve or adjust the flow rate.

[0042] In the body 10, a primary side opening 21 through which the fluid flows into the flow rate adjustment side is formed on the seat ring 11 side of the inlet 10a, while a secondary side opening 22 through which the fluid flows out is formed on the seat ring 11 side of the outlet 10b. The body 10 is configured in a so-called flow-under type structure, and this flow-under type body 10 allows the fluid flowing in from the primary side opening 21 to pass through the seat ring 11 from bottom to top and flow out from the secondary side opening 22.

[0043] The seat ring 11 is formed into an annular shape from a metal material such as a stainless steel alloy, and has an annular plate portion 23 formed with an outer diameter that allows it to be inserted into the valve seat retaining portion 17, and an annular protrusion portion 24 formed and protruding downward from the inner periphery of the annular plate portion 23. The annular protrusion portion 24 has an outer diameter that allows it to be inserted into the inner periphery of the primary side opening 21 formed in the lower part of the valve seat retaining portion 17, and a tapered surface 25 is formed on the upper inner periphery of the annular plate portion 23. When the valve is closed, the tip side of the valve body portion 18 of the plug 16 comes into contact (abuts) with the tapered surface 25, enabling sealing, and when the valve is open, the distance between the valve body portion 18 and the tapered surface can be adjusted to enable precise flow rate adjustment.

[0044] The gasket 12 is made of a resin material such as PTFE (polytetrafluoroethylene) and is formed into an annular shape with dimensions approximately the same as the outer diameter of the annular plate portion 23 of the seat ring 11, and is fitted between the seat ring 11 and the valve seat retaining portion 17. As a result, the gap between the body 10 and the seat ring 11 is sealed by the gasket 12, preventing back leakage from this area.

[0045] The seat retainer 13 is formed in a cylindrical shape from a metal material such as a stainless steel alloy, and its cylindrical side peripheral wall portion 30 is provided with a plurality of opening holes 31 in the circumferential direction, through which fluid can pass. The seat retainer 13 is placed on the upper surface of the seat ring 11 mounted in the body 10, and is mounted in the mounting recess 10c substantially concentrically with the seat ring 11. When the valve is open, fluid flows into the in-body flow path from the primary side opening 21 through the opening holes 31 and flows out to the secondary side from the secondary side opening 22.

[0046] The seat retainer 13 is provided so that adjacent opening holes 31 have mutually different shapes in the circumferential direction, and in this example, at least one of these opening holes 31 is provided in a vertically asymmetrical shape with an opening area larger on the seat ring 11 side than on the bonnet 14 side. Here, "the opening area is larger on the seat ring 11 side than on the bonnet 14 side" means that when comparing the areas of the openings of the opening hole 31 in ranges equidistant from the end on the bonnet 14 side and the end on the seat retainer 13 side, the opening on the seat retainer 13 side is larger than the opening on the bonnet 14 side. The seat retainer 13 is fixed in place in a state where the opening hole portion 31 having the asymmetrical shape in the up-down direction is disposed so as to face the secondary side opening 22 of the body 10 .

[0047] Furthermore, among the openings 31, at least the openings 31 having an asymmetrical shape in the vertical direction are formed in a generally triangular shape when viewed from the front.

[0048] Describing the seat retainer 13 in more detail, as shown in FIG. 3, the opening hole 31 having an asymmetrical shape in the vertical direction is formed in a roughly isosceles triangle shape in the mounting direction of the seat retainer 13, and the other opening hole portions 31 are also provided in an asymmetrical shape in the vertical direction, and are provided at a total of four locations at 90° intervals around the circumferential direction of the side peripheral wall portion 30 of the seat retainer 13.

[0049] In this example, the opening holes 31 are provided so as to have a different shape from adjacent opening holes 31 in the circumferential direction, and two opening holes 31a (hereinafter referred to as "opening holes with an upper apex") having a larger opening area on the seat ring 11 side than on the bonnet 14 side and having a generally triangular shape with the apex facing up and two opening holes 31b (hereinafter referred to as "opening holes with an upper apex") having a larger opening area on the bonnet 14 side than on the seat ring 11 side and having a generally triangular shape with the apex facing down are alternately arranged in the circumferential direction. These four opening holes 31 are provided in the shape of generally isosceles triangles that are generally congruent to each other, and the opening hole 31a (with the apex facing up) is provided opposite the secondary-side opening 22, and the adjacent opening holes 31 are arranged so as to be upside down relative to this opening hole 31a. In this example, the total area of ​​the opening areas of the four opening hole portions 31 is set to be larger than the opening area of ​​the secondary side opening portion 22.

[0050] Although the opening hole 31 of this embodiment has a substantially triangular shape, the corners of the triangle are rounded, and in particular, the two corners on the base side are largely rounded, so that when a compressive force is applied in the vertical direction of the seat retainer 13, stress does not concentrate near the corners, making it less likely that breakage will originate from the corners and improving the durability of the seat retainer 13. Also, in terms of ease of flow, the rounded corners of the opening hole 31 prevent the fluid from suddenly passing through a narrow section, making it less likely that a sudden change in flow velocity or the generation of a vortex, and allowing the fluid to pass through the opening hole 31 smoothly.

[0051] By forming the above-mentioned four approximately triangular opening hole portions 31, pillar portions 32, which will be described later, are provided at four locations between adjacent opening hole portions 31. As described above, since the opening hole portions 31 are approximately isosceles triangular, adjacent opening hole portions 31 are point-symmetric, and the same number of pillar portions 32 as the number of opening hole portions 31 are provided between each opening hole portion 31. In this example, the total cross-sectional area of ​​the pillar portions 32 in a direction perpendicular to the central axis C of the seat retainer 13 is set to be approximately constant in the portion where the opening hole portions 31 are formed.

[0052] 4 is an enlarged longitudinal cross-sectional view of a portion of the valve body 2, showing the cross-section on the secondary side opening 22 side. The seat retainer 13 is disposed in the body 10 so that one of the opening holes 31a, the vertex of which is at the top, is positioned opposite the secondary side opening 22.

[0053] In this case, as shown in Figure 5, the opening hole portion 31 having an asymmetrical shape in the vertical direction, i.e., the opening hole portion 31a with its apex at the top, is positioned inside the secondary side opening portion 22 shown by the dashed line in the fluid flow direction.

[0054] The secondary-side opening 22 is the boundary between the body 10 and the outlet 10b, and as shown in the figure, has an oval shape that is long in the horizontal direction. This is because the opening area of ​​the secondary-side opening 22 is gradually narrowed from the secondary-side opening 22 toward the outlet 10b to prevent sudden changes in flow velocity and pressure at the secondary-side opening 22 and to allow the fluid to flow smoothly from inside the body 10. The secondary-side opening 22 has an oval shape so that its height is equal to the height of the body 10 and is as large as possible, equal to or greater than the total opening of the opening holes 31a of the seat retainer 13, and its width narrows from there toward the circular outlet 10b.

[0055] The seat retainer 13 described above has a bonnet-side annular portion 33 arranged on the bonnet 14 side, a seat ring-side annular portion 34 arranged on the seat ring 11 side, and the plurality of pillar-shaped portions 32 described above connecting these annular portions 33, 34, and is configured to have a generally cylindrical shape as a whole. As described above, the opening hole 31 through which a fluid can pass is formed between adjacent pillar-shaped portions 32. In other words, the seat retainer 13 is provided with a cylindrical side peripheral wall portion 30 and a plurality of pillar-shaped portions 32.

[0056] As described above, in this embodiment, the opening hole portions 31 are formed in the shape of an approximately isosceles triangle, and columnar portions 32 are provided between these opening hole portions 31, so that each columnar portion 32 has a substantially constant width between the bonnet side annular portion 33 and the seat ring side annular portion 34 and is formed at an angle with respect to the axial direction of the central axis C of the seat retainer 13.

[0057] In these columnar portions 32, "a substantially constant width from the bonnet-side annular portion 33 to the seat ring-side annular portion 34" means that the width between the opposing sides of adjacent openings 31 is substantially constant, excluding the rounded corners of the openings 31. This width does not need to be a strictly constant width, and the requirements of the present invention are met as long as the width is approximately the same, rather than being narrower on one side and wider on the other, depending on the shape of the openings 31.

[0058] Furthermore, in terms of the vertical width, the bonnet-side annular portion 33 is larger than the seat ring-side annular portion 34. As a result, when the bonnet 14 presses the seat retainer 13 toward the seat ring 11, the load applied from the bonnet 14 to the pillar portions 32 can be received by the bonnet-side annular portion 33, making it possible to prevent stress from concentrating on the pillar portions 32 and causing bending or the like.

[0059] Furthermore, since adjacent opening hole portions 31 are arranged in a point-symmetrical shape with respect to each other, adjacent columnar portions 32 are arranged in the circumferential direction of the seat retainer 13 so that they are inclined in opposite directions relative to the center axis C of the seat retainer 13.

[0060] 1 and 2 is made of the same metal material as the body 10, such as carbon steel casting, and has a generally cylindrical shape that can be mounted on the top of the body 10, and the actuator 3 is attached to the body 10 via this bonnet 14. A plug insertion hole 40 is provided on the lower inner periphery of the bonnet 14, and an annular mounting portion 41 for mounting the plug guide 15 is formed in the shape of an enlarged groove on the opening side of the lower inner periphery of this plug insertion hole 40. An annular projection 42 is formed in the center of the bottom side of the bonnet 14 so as to protrude slightly, and the upper end opening side of the seat retainer 13 is provided on the outer periphery of this annular projection 42 so that it can be attached.

[0061] Plug guide 15 is made of a metal material such as a stainless steel alloy and is formed into a cylindrical shape with an appropriate thickness as a separate body from bonnet 14, and is attached to bonnet 14. The outer periphery of plug guide 15 has an outer diameter that allows it to be press-fitted into annular mounting portion 41, and plug guide 15 is attached to plug insertion hole 40 with its lower end welded to bonnet 14 by spot welding, thereby fixing it to bonnet 14 in a state where it is prevented from slipping out. The inner diameter of plug guide 15 is sized to allow plug 16 to slide up and down, thereby enabling it to guide the movement of plug 16.

[0062] The bonnet 14 is attached to the opening 10d of the body 10 with mounting bolts and nuts 44 via a bonnet gasket 43 made of a resin material such as PTFE, and the bonnet 14 and body 10 are integrated in a sealed state. As a result, the seat ring 11 is pressed by the bonnet 14 via the seat retainer 13, and is fixed between the bonnet 14 and the body 10.

[0063] The actuator 3 is, for example, a diaphragm-type pneumatic actuator. In this case, it is smaller and lighter than actuators of other structures that use air pressure, such as cylinder-type pneumatic actuators, and allows for fine flow rate adjustment. The actuator 3 is provided with an output shaft 50, which is attached so as to be able to move forward and backward in the output direction via a bearing 52. A plug 16 is connectably provided to the output shaft 50, and the plug 16 is provided through the output shaft 50 so as to be able to move up and down relative to the seat ring 11. Furthermore, the actuator 3 is provided with a rotary handle 51 for manual operation, and in an emergency or other situation where the actuator 3 cannot be operated automatically, the plug 16 can be advanced or retreated by manually operating this rotary handle 51.

[0064] The actuator 3 is attached to the top of the valve body 2 via a frame-shaped yoke 55. In this case, a mounting hole 56 into which a bearing 52 can be fitted is provided on the top surface of the yoke 55, and with the output shaft 50 and bearing 52 inserted into this mounting hole 56, the actuator 3 is attached to the top surface of the yoke 55 via this bearing 52. On the other hand, the upper part of the bonnet 14 of the valve body 2 is fixedly provided to the lower part of the yoke 55, thereby integrating the valve body 2 and the actuator 3 by the yoke 55 to form the valve body 1.

[0065] In this case, the plug 16 of the valve body 2 and the output shaft 50 of the actuator 3 are connected concentrically by a connector 57 for connection, and are provided so that the output from the output shaft 50 can be transmitted to the plug 16 in a centered state. In this way, by connecting the plug 16 and the output shaft 50 using the connector 57, a plug rod 60 is formed in which the plug 16 and the output shaft 50 are integrated, and this plug rod 60 functions as a plug.

[0066] In addition, the opening hole portion of the seat retainer 13, which is asymmetrical in the vertical direction, may be formed in a shape other than an approximately triangular shape, as long as it is asymmetrical in the vertical direction in the installation direction of the seat retainer 13.For example, the opening hole portion can be formed in various shapes such as a trapezoidal shape or a semi-cylindrical shape. Furthermore, the vertically asymmetric opening hole portion may have a shape other than a line-symmetric shape in the left-right direction.

[0067] Furthermore, the opening hole portion adjacent to the opening hole portion having an asymmetrical shape in the vertical direction and other opening hole portions may each be provided in a shape different from the opening hole portion having an asymmetrical shape in the vertical direction, and each opening hole portion may be provided in any shape, such as a square or a circle. In either case, it is desirable to form each opening hole so that the total cross-sectional area of ​​the columnar portion 32 in a cross section perpendicular to the central axis C is always approximately constant.

[0068] The number of apertures may be increased or decreased from four, and in this case, the same number of pillar portions as the number of apertures are formed. When the apertures are formed in a line-symmetrical shape, such as an approximately isosceles triangle, it is preferable to provide an even number of apertures on the side peripheral wall of the seat retainer. In this case, the apertures are alternately arranged in up-down opposite directions, and adjacent pillar portions can be arranged inclined in opposite directions relative to the axial direction of the seat retainer in the circumferential direction of the seat retainer.

[0069] Furthermore, the actuator 3 may be of a type other than a diaphragm-type pneumatic actuator, and various other actuators such as a cylinder-type pneumatic actuator may also be used.

[0070] Next, the operation of the regulator valve of the above embodiment of the present invention will be described. 1 and 2, the valve body 1 is configured so that the seat ring 11 is fixed by pressing it from above against the valve seat holder 17 side with the bonnet 14 via the seat retainer 13, so that by loosening the bolts and nuts 44 and removing the bonnet 14 from the body 10, the seat retainer 13 can be pulled out of the mounting recess 10c, making it possible to attach or detach the seat retainer 13. This makes it possible to easily remove the seat ring 11 from the body 10 and perform maintenance on or replace the seat ring 11 depending on the degree of wear of the seat ring 11, etc.

[0071] When the plug 16 of the valve body 1 is operated from the valve closed state to the valve open direction under the control of the actuator 3, the degree of the gap (size of the gap) between the tapered portion 18c of the valve body 18 and the tapered surface 25 of the seat ring 11 is adjusted according to the advance / retract state of the plug 16, and the flow rate is adjusted according to the size of this gap, and fluid flows into between the valve body 18 and the seat ring 11 from the inlet 10a through the primary side opening 21. The fluid then flows through a plurality of substantially triangular openings 31 formed in the cylindrical side peripheral wall 30 of the seat retainer 13 toward the secondary opening 22, and from this secondary opening 22 toward the outlet 10b.

[0072] In the seat retainer 13, a plurality of opening holes 31 are provided in the shape of an approximately isosceles triangle when viewed from the front, which is asymmetrical in the top and bottom directions in the mounting direction of the seat retainer 13, and adjacent opening holes 31a with their vertices at the top and opening holes 31b with their vertices at the bottom are arranged alternately in the circumferential direction of the seat retainer 13 so that adjacent opening holes 31 are oriented upside down in opposite directions in the circumferential direction of the seat retainer 13, and these have different shapes from each other, so that a large total opening area can be secured by the opening holes 31 throughout the entire mounting direction of the seat retainer 13.

[0073] As a result, the opening area of ​​the opening hole portion 31 can be ensured to be sufficiently large compared to the opening area created in the gap between the valve body portion 18 and the seat ring 11, over the entire opening range of the valve body from the initial small opening when the valve is opened to the full opening, so that the flow of fluid whose flow rate is adjusted by the valve body portion 18 and the seat ring 11 is not obstructed by the opening hole portion 31, and flows smoothly toward the secondary side opening 22.

[0074] Furthermore, at least one of the opening hole portions 31 is formed as an opening hole portion 31a having an asymmetrical shape in the up and down direction, with the apex at the top, and the opening hole portion 31 opposite this opening hole portion 31a is also formed as an opening hole portion 31a having the apex at the top, so that the opening area by the seat retainer 13 can be secured and a sufficient flow rate can be ensured, especially when the opening is small.

[0075] In the case of a flow-under type control valve in which the fluid passes from below to above the seat ring 11, as in this embodiment, the fluid flows easily through the region below the seat retainer 13 and is less likely to flow through the region above it. In particular, when the opening of the valve body 18 is small, the flow of the fluid tends to concentrate in the region below the seat retainer 13. In the present invention, the opening hole 31a facing the secondary-side opening 22 is provided so that the opening area on the lower side is larger, which means that the opening in the part where the flow is particularly easy is enlarged, and it is possible to ensure a sufficient flow rate without making the hole too large.

[0076] The seat retainer 13 is positioned relative to the body 10 so that one of the opening holes 31a with the upper vertex faces the secondary-side opening 22. Therefore, the fluid that has passed through the gap between the valve body 18 and the seat retainer 13 and has its flow rate adjusted flows linearly from this opening hole 31a toward the secondary-side opening 22. At the same time, the fluid flows out of the other opening hole 31a and the opening hole 31b with the two lower vertices, allowing the fluid to flow while achieving a high Cv value. Since one opening hole 31a is positioned closest to the secondary-side opening, the fluid flows more easily at small openings, providing excellent flow characteristics from small openings to full openings.

[0077] The total opening area of ​​the four opening hole portions 31 (two opening hole portions 31a and two opening hole portions 31b) is set to be larger than the opening area of ​​the secondary side opening 22, so that the opening hole portions 31 do not obstruct the flow of fluid whose flow rate is adjusted by the valve body portion 18 and the seat retainer 13, and the flow rate-adjusted fluid flows smoothly from the secondary side opening 22 through the four opening hole portions 31.

[0078] At this time, the opening hole portion 31a, whose apex faces the secondary side opening 22, is positioned inside the secondary side opening 22 in the direction of fluid flow, so that the fluid that passes through this opening hole portion 31a is prevented from directly colliding with the peripheral wall of the secondary side opening 22, and flows in a straightened state from the secondary side opening 22 toward the downstream side.

[0079] The seat retainer 13 is formed into a generally cylindrical shape by a bonnet-side annular portion 33, a seat ring-side annular portion 34, and a plurality of pillar-shaped portions 32, and the opening holes 31 through which the fluid passes are formed between adjacent pillar-shaped portions 32. Therefore, by setting the shape and size of each of these opening holes 31, the shape and size of the pillar-shaped portions 32 can also be set at the same time.

[0080] In this case, for example, as in the seat retainer 13 of this embodiment, the opening hole portion 31 is made to be approximately isosceles triangular in shape, and adjacent opening hole portions 31a and 31b are arranged in upside-down opposite directions, so that each columnar portion 32 located between these opening hole portions 31a and 31b has an approximately constant width from the bonnet side annular portion 33 to the seat ring side annular portion 34, and is formed so as to be inclined with respect to the axial direction of the approximately cylindrical seat retainer 13.

[0081] This allows the total cross-sectional area of ​​the columnar portions 32 in a direction perpendicular to the central axis C to be maintained at a substantially constant size in the direction of the central axis C while minimizing the size of the shape, width, etc. of the columnar portions 32, and makes it possible to uniformize the ratio between the portion with the open holes 31 and the portion without the open holes 31 along the central axis of the seat retainer 13. Therefore, it is possible to manufacture a seat retainer 13 in which the strength of the side peripheral wall portions 30 of the seat retainer 13 in the direction of the central axis C due to the columnar portions 32 is set to a substantially constant value, and which prevents localized stress from acting on parts of the columnar portions 32 when a pressing force is applied from the hood 14 side to the seat ring 11 side, thereby distributing stress evenly across the entire columnar portions 32.

[0082] By providing each opening hole portion 31 in a simple, approximately triangular shape, the seat retainer 13 can be easily formed, and for example, when the seat retainer is formed by casting, the number of opening holes can be easily changed.

[0083] The pillar-shaped portions 32 are formed at an angle in the circumferential direction of the seat retainer 13 so that adjacent ones are in opposite directions to each other, thereby ensuring the opening area on the seat ring 11 side of the opening hole portion 31a arranged opposite the secondary side opening 22.On the other hand, the multiple pillar-shaped portions 32 form a so-called truss-structured side peripheral wall portion 30, which connects the bonnet-side annular portion 33 and the seat ring-side annular portion 34.

[0084] These structures make it possible to secure a large opening area for the opening hole 31 while minimizing the size of the columnar portion 32, thereby increasing the strength of the entire seat retainer 13. In particular, the strength in the pressing direction by the bonnet 14 is improved, which effectively distributes stress and improves the durability of the seat retainer 13 after it is attached to the body 10.

[0085] During flow control when the valve is open, in the globe valve type valve body 2, when fluid flows under from the inlet 10a and fluid pressure is applied from below the valve body 18, even if this fluid pressure rises, vibration on the valve body 18 side can be suppressed, making it possible to maintain high-precision flow control, and also suppressing the generation of turbulence on the secondary side (outlet 10b side) due to core vibration on the valve body 18 side.

[0086] If the internal parts of the valve body 2 deteriorate or wear due to long-term use, the bolts and nuts 44 can be loosened to remove the bonnet 14 side from the body 10, making it easy to replace or maintain the seat ring 11 as well as the seat retainer 13, gasket 12, plug 16, bonnet gasket 43, and other internal parts.

[0087] The above describes in detail the embodiments of the present invention, but the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the spirit of the invention described in the claims of the present invention. [Explanation of symbols]

[0088] 1 Valve body 10 Body 11 Seat ring 13 Seat retainer 14. Bonnet 16 Plug 17 Valve seat retainer 18 Valve body 21 Primary side opening 22 Secondary side opening 30 Side peripheral wall 31 Opening hole 31a: An opening hole portion having a substantially triangular shape with its vertex at the top (an opening hole portion having its vertex at the top) 31b An opening hole portion having a substantially triangular shape with the apex downward (an opening hole portion having the apex downward) 32 Columnar part 33 Bonnet side annular part 34 Seat ring side annular portion

Claims

1. a plug having a valve body at its tip that is movable toward and away from the seat ring, and capable of adjusting the degree of contact and separation between the valve body and the seat ring to control fluid; the body having a primary-side opening through which fluid flows in and a secondary-side opening through which fluid flows out; a cylindrical side wall of the seat retainer having a plurality of openings that are adjacent to each other in the circumferential direction, the cylindrical side wall of the seat retainer having a plurality of openings through which fluid can pass, at least one of which has an asymmetrical shape in the up-down direction and has a larger opening area on the seat ring side than on the bonnet side; and the seat retainer having a plurality of openings that are asymmetrical in the up-down direction and have a larger opening area on the seat ring side than on the bonnet side, the seat retainer being disposed such that the asymmetrical opening of the openings faces the secondary-side opening of the body.

2. The regulator valve according to claim 1 , wherein the seat retainer is provided so that adjacent openings have different shapes in the circumferential direction.

3. The regulating valve according to claim 1 or 2, wherein at least the vertically asymmetric opening hole portion among the opening hole portions is formed in a generally triangular shape in a front view.

4. The control valve according to claim 1 , wherein the vertically asymmetric opening hole portion is disposed inside the secondary opening portion in the fluid flow direction.

5. 2. The control valve according to claim 1, wherein the body is of a flow-under type in which fluid flowing in from the primary side opening passes through the seat ring from below to above and flows out from the secondary side opening.

6. a plug having a valve body at its tip that is movable toward and away from the seat ring, and fluid control is enabled by adjusting the degree of contact and separation between the valve body and the seat ring; the seat retainer is generally cylindrical and is made up of a bonnet-side annular portion disposed on the bonnet side, a seat ring-side annular portion disposed on the seat ring side, and a plurality of pillar-shaped portions connecting these annular portions, and an opening hole through which fluid can pass is formed between adjacent pillar-shaped portions, and each of the pillar-shaped portions has a generally constant width from the bonnet-side annular portion to the seat ring-side annular portion and is formed at an angle with respect to the axial direction of the generally cylindrical seat retainer.

7. The regulator valve according to claim 6 , wherein adjacent ones of the pillar-shaped portions are inclined in opposite directions relative to the axial direction of the seat retainer in the circumferential direction of the seat retainer.

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