Regulating valve having heat dissipation plates

Abstract

The present invention provides a regulating valve that facilitates maintenance while protecting a packing arranged around a stem from the influence of the temperature of a fluid by the heat dissipation effect of heat dissipation plates. The regulating valve has: a body accommodating a valve element; an operation unit disposed on an upper portion of the body; a stem connecting the valve element and the operation unit; and a bonnet having a flange portion and a cylindrical portion through which the stem extends, the regulating valve having a packing arranged around the stem. A plurality of disk-shaped heat dissipation plates are provided on the cylindrical portion of the bonnet, and the heat dissipation plate closest to the flange portion has an outer diameter smaller than the outer diameters of the other heat dissipation plates.

Description

Control Valve Having Heat Dissipation Plates

[0001] The present invention relates to a control valve used for controlling high-temperature fluid, and particularly relates to a control valve that is easy to maintain and suitable for preventing packing deterioration caused by high temperature.

[0002] In a control valve that controls fluid flow by opening and closing the valve, packing is arranged around the stem at a position before the stem is exposed from the bonnet, to prevent fluid from leaking to the outside. Since this packing is usually made of heat-sensitive material, in control valves installed in high-temperature fluid flow paths, the influence of heat from the flow path is reduced to prevent deterioration of the packing.

[0003] Patent Document 1 discloses a configuration in which a multi-stage fin is provided on an upper cover of a control valve to protect a seal portion and the like from the influence of temperature from fluid. Patent Document 2 discloses a configuration of a heat dissipation fin with excellent heat dissipation effect, which is provided at a gland portion of a high-temperature valve.

[0004] Japanese Utility Model Publication No. 58-86976; Japanese Utility Model Publication No. 47-39366

[0005] In a control valve installed in a high-temperature fluid flow path, it is desirable to increase the distance between the flow path and the packing as much as possible in order to reduce heat transfer to the packing arranged around the stem. On the other hand, it is desirable to reduce the overall size of the control valve as much as possible.

[0006] Therefore, conventionally, in a control valve comprising: a body that accommodates a valve element; an operating unit installed on an upper part of the body via a bonnet; a stem that connects the valve element and the operating unit and opens and closes the valve element by the operation of the operating unit; and a bonnet having a flange portion and a cylindrical portion, the bonnet being attached to the body at the flange portion by a connecting member, with the stem penetrating through the inside of the cylindrical portion, wherein packing is arranged around the stem at a position before the stem is exposed to the outside of the bonnet, a plurality of heat dissipation plates are installed on the cylindrical portion of the bonnet as shown in Patent Documents 1 and 2.

[0007] In this case, to reduce the overall size of the control valve, it is preferable to shorten the distance between the heat sink and the flange. However, when connecting the flange of the hood to the body with connecting members such as bolts and nuts, the heat sink closest to the flange gets in the way of the connection work.

[0008] Furthermore, while increasing the outer diameter of the heat sink is preferable to enhance its heat dissipation effect, if the heat sink protrudes beyond the flange, it is more likely to come into contact with workers or surrounding objects during transportation or after installation, potentially causing malfunctions and increasing the risk of injury.

[0009] Furthermore, because the control valve is opened and closed frequently to adjust the fluid flow rate, the valve body and seat ring inside the body are prone to deterioration. Therefore, regular maintenance is necessary to check the degree of deterioration and replace parts, and it is preferable that the bonnet and body can be easily disassembled and reassembled.

[0010] Furthermore, while the above-mentioned control valves are sometimes installed outdoors, water accumulating on the heat sink during rain can cause corrosion and soiling such as moss. The present invention aims to provide a control valve that protects the packing placed around the stem from the effects of fluid temperature due to the heat dissipation effect of the heat sink, while also facilitating maintenance.

[0011] The invention according to claim 1 of the present application is a control valve comprising a body housing a valve body, an operating unit installed on the upper part of the body via a bonnet, a stem connecting the valve body and the operating unit and opening and closing the valve body by the operation of the operating unit, and a bonnet having a flange portion and a cylindrical portion, attached to the body by a connecting member at the flange portion, and through which the stem passes inside the cylindrical portion, wherein a packing is arranged around the stem in the portion just before the stem is exposed to the outside of the bonnet, wherein the cylindrical portion of the bonnet is provided with a plurality of disc-shaped heat sinks, the heat sink closest to the flange portion has an outer diameter smaller than the outer diameter of the other heat sinks, and is provided so as not to overlap with the connecting member when viewed from above.

[0012] The invention according to claim 2 of this application is a control valve in which the heat sink closest to the flange portion has an outer diameter that fits inside the connecting member, and the other heat sinks have an outer diameter that fits inside the outer circumference of the flange portion.

[0013] The invention according to claim 3 of the present application is a control valve further provided inside the body, which includes a seat ring that opens and closes a flow path when a valve body moves toward and away from it, and a seat retainer interposed between the seat ring and the bonnet, which transmits the pressing force of the bonnet to the seat ring and fixes the seat ring to the body.

[0014] The invention according to claim 4 of the present application is also a control valve in which the surface of the heat sink on the operating part side is inclined toward the body side from the cylindrical part side toward the outer circumference side.

[0015] The invention according to claim 5 of the present application is also a control valve in which the heat sink is integrally formed with the cylindrical portion.

[0016] The control valve of the present invention is provided with multiple disc-shaped heat sinks on the cylindrical portion of the hood, and the heat sink closest to the flange portion has a smaller outer diameter than the other heat sinks and is positioned so as not to overlap with the connecting member when viewed from above. As a result, when connecting the flange portion of the hood to the body with connecting members such as bolts and nuts, the heat sink closest to the flange portion does not get in the way of the connection work, making the work easier.

[0017] Furthermore, when bolts and nuts are used as connecting members, the connecting members protrude from the flange portion. Therefore, by positioning the heat sink closest to the flange portion so that it does not overlap with the connecting member when viewed from above, the connecting member becomes completely exposed to the outside, and a heat dissipation effect from the connecting member can be expected.

[0018] Furthermore, because the heat sink closest to the flange no longer interferes with the connection work when joining the hood flange to the body with bolts, nuts, and other connecting components, disassembly and assembly of the hood and body can be made easier, and regular maintenance can be easily performed.

[0019] In the control valve according to claim 2, the heat sink closest to the flange has an outer diameter that fits inside the connecting member, and the other heat sinks have an outer diameter that fits inside the outer circumference of the flange. As a result, the heat sinks do not protrude outside the flange, eliminating the risk of malfunction or increased danger from contact by workers or surrounding objects during transportation or after installation. Furthermore, by increasing the size of the other heat sinks within the range of having an outer diameter that fits inside the outer circumference of the flange, the heat dissipation effect is improved.

[0020] The control valve according to claim 3 is provided with a seat ring inside the body that opens and closes the flow path by moving the valve body toward and toward the body, and a seat retainer interposed between the seat ring and the hood that transmits the pressing force of the hood to the seat ring and fixes the seat ring to the body. Therefore, compared to a typical control valve in which the seat ring is fixed to the body by screwing or press-fitting, the removal of the seat ring is extremely easy, resulting in excellent maintainability. As a result, in the control valve according to claim 3, as described above, the heat sink closest to the flange portion has an outer diameter and shape that does not interfere with the coupling work by the connecting member, and does not get in the way when removing the connecting member. Combined with the ease of disassembling and assembling the body and hood, it has excellent maintainability.

[0021] Furthermore, in the control valve according to claim 4, the surface of the heat sink on the operating part side is sloped toward the body side from the cylindrical part side toward the outer circumference side, so when installed outdoors, water does not accumulate on the heat sink due to rain, and corrosion and dirt such as moss are reduced.

[0022] Furthermore, the control valve according to claim 5 has an improved heat dissipation effect because the heat sink is integrally formed with the cylindrical portion. In addition, when the heat sink is integrally formed with the cylindrical portion, it was previously necessary to connect the bonnet to the body with the heat sink already formed, which made assembly difficult. However, according to the present invention, the heat sink closest to the flange portion does not overlap with the connecting member, making it easier to connect the bonnet to the body.

[0023] This is a diagram showing the control valve according to the present invention. This is a diagram showing a cross-section of the body and bonnet portion of Figure 1. This is a cross-sectional view taken from line A-A in Figure 1.

[0024] The control valve according to the present invention will be described below with reference to Figures 1, 2, and 3. The control valve according to the present invention can be used in a fluid temperature range of approximately -45 to 500°C and is particularly suitable for controlling high-temperature fluids. The fluids it can be used with include water, steam, air, petroleum raw materials such as crude oil and naphtha, and various chemical substances. The control valve according to the present invention is installed indoors or outdoors and is mainly driven by air.

[0025] As shown in Figures 1 and 2, the control valve of the present invention comprises a body 1 housing a valve body 2, an operating unit 5 installed on the upper part of the body 1 via a bonnet 3, a stem 4 connecting the valve body 2 and the operating unit 5 and opening and closing the valve body 2 by the operation of the operating unit 5, and a bonnet 3 having a flange portion 8 and a cylindrical portion 7, attached to the body 1 by a connecting member 9 at the flange portion 8, with the stem 4 passing through the inside of the cylindrical portion 7, and a packing 12 arranged around the stem 4 in the portion just before the stem 4 is exposed to the outside of the bonnet 3.

[0026] In this embodiment, the case in which a globe valve is used as a control valve will be explained as an example. Although the present invention is mainly used for globe valves, it can also be applied to gate valves, butterfly valves, ball valves, diaphragm valves, etc. Globe valves are particularly suitable as control valves because they have excellent shut-off performance and flow rate control.

[0027] In the control valve shown in Figure 1, the body 1 has an opening at the top and has a fluid inlet 10, an outlet 11, and a flow path connecting them, and houses a valve body 2 inside. The movement of this valve body 2 up and down controls the opening and closing of the flow path and adjusts the fluid flow rate.

[0028] The valve body 2 is connected by a stem 4 to an operating unit 5 located on the upper part of the body 1. The operating unit 5 operates the valve body 2 by driving the stem 4 up and down based on signals from a controller such as a flow meter installed in the fluid piping.

[0029] A bonnet 3 is installed in the opening at the top of the body 1. The bonnet 3 has a flange portion 8 and a cylindrical portion 7, and the flange portion 8 is attached to the opening at the top of the body 1 by a connecting member 9, thereby closing the opening.

[0030] The bonnet 3 has a cylindrical portion 7 integrally formed on the upper part of the flange portion 8. A stem 4 passes through the inside of the cylindrical portion 7, thereby connecting the valve body 2 and the operating portion 5 through the opening in the body 1 via the stem 4.

[0031] The connecting member 9 that connects the flange portion 8 to the opening in the body 1 can be a bolt and nut or a clamp. The control valve requires periodic maintenance for purposes such as checking the deterioration of the valve body 2 and seat ring 13 inside the body 1 and replacing parts. Therefore, a bolt and nut that allows for easy disassembly and assembly of the bonnet 3 and the body 1 is suitable as the connecting member 9.

[0032] As shown in Figure 2, the body 1 is provided with a seat ring 13 that opens and closes the flow path when the valve body 2 moves toward and toward it, and a seat retainer 14 interposed between the seat ring 13 and the bonnet 3, which transmits the pressing force of the bonnet 3 to the seat ring 13 and fixes the seat ring 13 to the body 1. The seat ring 13 is formed in an annular shape from a metal material such as stainless steel alloy, and when the valve is closed, the valve body 2 comes into contact with its surface, thereby sealing the fluid.

[0033] The seat retainer 14 is formed in a cylindrical shape from a metal material such as stainless steel alloy, and has an opening through which fluid flows when the valve is open. It is placed on the upper surface of the seat ring 13 which is installed inside the body 1. By being interposed between the seat ring 13 and the bonnet 3, when the bonnet 3 is attached to the body 1, it transmits the pressing force from the bonnet 3 to the seat ring 13, thereby fixing the seat ring 13 to the body 1.

[0034] In the control valve of the present invention, the seat ring 13 is fixed to the body 1 by the pressing force from the seat retainer 14. Compared to control valves in which the seat ring 13 is fixed to the body 1 by screwing or press-fitting, the seat ring 13 is very easy to remove, resulting in excellent maintainability. Therefore, the heat sink 6a closest to the flange portion 8 has an outer diameter and shape that does not interfere with the joining work by the connecting member 9, and does not get in the way of tools when removing the connecting member 9. Combined with the ease of disassembly and assembly of the body 1 and bonnet 3, this results in excellent maintainability.

[0035] In the control valve of the present invention, a packing 12 is placed around the stem 4 at the point just before the stem 4 is exposed to the outside of the bonnet 3, preventing fluid from leaking out. The material of the packing 12 can be, for example, polytetrafluoroethylene (PTFE), expanded graphite, or a combination thereof, and can be selected depending on the temperature expected in the area where the packing 12 is placed. The heat resistance temperature of the packing 12 is, for example, 260°C or less for PTFE, and approximately -270 to 450°C for expanded graphite. The material of the body 1 and bonnet 3 is carbon steel casting, and the material of the stem 4 is stainless steel alloy.

[0036] In this invention, a plurality of disc-shaped heat sinks 6 are provided on the cylindrical portion 7 of the bonnet 3. The heat sinks 6 are made of metal, and by increasing the surface area, it is possible to lower the temperature of the area where the packing 12 is placed to below the heat resistance temperature of the packing material, even with natural air cooling. The temperature of the area where the packing 12 is placed is preferably 150°C or less, more preferably 140°C or less, and even more preferably 130°C or less, in order to reduce the thermal impact on the operating section 5 where the actuator etc. is installed, and to increase the freedom of selection of the material of the packing 12. The number of heat sinks 6 etc. is optimized to satisfy these conditions.

[0037] In the control valve of the present invention, the heat sink 6a closest to the flange portion 8 has an outer diameter smaller than the outer diameter of the other heat sinks 6b, and is provided so as not to overlap with the connecting member 9 when viewed from above. Here, "viewed from above" means the view of the control valve bonnet 3 from the operating part side 5 towards the body 1, as shown in Figure 3.

[0038] In this invention, only the heat sink 6a closest to the flange portion 8 has an outer diameter smaller than the outer diameters of the other heat sinks 6b. To enhance the heat dissipation effect, a larger outer diameter of the heat sink 6 is preferable. Therefore, it is desirable to make the outer diameters of the other heat sinks 6b as large as possible.

[0039] As shown in Figures 2 and 3, the heat sink 6a closest to the flange portion 8 is positioned so as not to overlap with the connecting member 9 when viewed from above. This ensures that when connecting the flange portion 8 of the bonnet 3 to the body 1 with connecting members 9 such as bolts and nuts, the heat sink 6a closest to the flange portion 8 does not interfere with the connection work, making the process easier. Furthermore, when bolts and nuts are used as connecting members 9, the connecting members 9 protrude from the flange portion 8, becoming completely exposed to the outside, and thus allowing for heat dissipation from the connecting members 9.

[0040] The outer diameter of the heat sink 6a closest to the flange portion 8 is smaller than the outer diameter of the other heat sinks 6b. However, in order to reduce the overall height and size of the control valve, it is effective to place the heat sink 6 as close to the body 1 as possible. Therefore, in order to optimize the heat dissipation effect, the overall compactness of the control valve, and the ease of disassembly and assembly of the body 1 and the bonnet 3, it is preferable to place the heat sink 6a closest to the flange portion 8 on the side of the cylindrical portion 7 at a position higher than the height of the connecting member 9 protruding from the surface of the flange portion 8. Since the outer diameter of the heat sink 6a closest to the flange portion 8 is smaller than the outer diameter of the other heat sinks 6b, and less likely to interfere with the connecting member 9, the heat sink 6a can be placed closer to the flange portion 8 than in conventional designs. If the heat sink 6a can be placed closer to the flange portion 8, the heat sink 6 can be positioned closer to the flow path, which also improves the heat dissipation effect.

[0041] Furthermore, in the control valve of the present invention, the heat sink 6a closest to the flange portion 8 has an outer diameter that fits inside the connecting member 9, and the other heat sinks 6b have an outer diameter that fits inside the outer circumference of the flange portion 8. Here, the heat sink 6a closest to the flange portion 8 has an outer diameter that fits inside the connecting member 9, so that it does not overlap with the connecting member 9 when viewed from above.

[0042] The larger the other heat sinks 6b are, the better the heat dissipation effect, which allows for a smaller distance between the flow path of the body 1 and the packing 12, and thus reduces the overall size of the control valve. However, if the heat sinks 6 protrude outward from the flange portion 8, there is a risk of malfunction or injury due to contact with workers or surrounding objects during transportation or after installation. Therefore, it is preferable that the other heat sinks 6b have an outer diameter that fits inside the outer circumference of the flange portion 8.

[0043] The other heat sinks 6b preferably have an outer diameter that fits inside the outer circumference of the flange portion 8, and more preferably have an outer diameter that fits inside the connecting member 9. An outer diameter that fits inside the connecting member 9 means that, when there are multiple connecting members 9, the outer diameter of each heat sink 6b does not overlap with any of the connecting members 9 in a plan view. For example, in the case of a square flange portion 8, connecting members 9 are usually placed at the four corners, but the diameter of each heat sink 6b may be smaller than the distance between diagonally placed connecting members 9. In this way, by having both the nearest heat sink 6a and the other heat sinks 6b have an outer diameter that fits inside the connecting member 9, it is possible to avoid increasing the size of the control valve in the planar direction by providing the heat sinks 6, and also to avoid the heat sinks protruding laterally. This makes it possible to achieve a compact design while obtaining a high heat dissipation effect, and further improve transportability and safety.

[0044] From the viewpoint of heat dissipation performance, it is desirable that the other heat dissipation plate 6b can have an outer diameter as large as possible within the allowable overall dimension. From this point of view, it is more preferable that the other heat dissipation plate 6b has an outer diameter that does not overlap with the connecting member 9 in a plan view, but overlaps with the connecting member 9 when viewed from a side direction. Taking the case where connecting members 9 are arranged at four corners of a square flange portion 8 as an example, when the outer diameter of the other heat dissipation plate 6b is smaller than the diagonal distance between the four connecting members 9 and larger than the distance between adjacent connecting members 9, the above-mentioned condition is satisfied. By satisfying this condition, it becomes possible to secure an outer diameter as large as possible for the heat dissipation plate 6b within the limited spatial volume sandwiched between the body 1 and the operation portion 5, and both heat dissipation performance and compactness can be achieved to the maximum extent.

[0045] On the other hand, for the heat dissipation plate 6a, the effect of the present invention can be obtained as long as its outer diameter is smaller than that of the above-mentioned other heat dissipation plate 6b. As a guideline for the outer diameter of the heat dissipation plate 6a, for example, when the connecting member 9 is used to couple the body 1 and the bonnet 3, it is more preferable that the outer diameter is reduced to such an extent that it does not interfere with the operation of the tool used for the coupling. The ratio of the outer diameter of the heat dissipation plate 6a is not particularly limited as long as it is smaller than that of the other heat dissipation plate 6b. However, from the viewpoint of maximizing both the heat dissipation effect and workability such as assembly, for a control valve exceeding 1 inch (2.54 cm) and less than 4 inches (10.16 cm), it is particularly preferable that the outer diameter is about 8 to 20% smaller than that of the other heat dissipation plate 6b.

[0046] Furthermore, the control valve of the present invention can achieve the aforementioned advantageous effects regardless of its size. For relatively small-sized control valves, since all outer diameters of the heat dissipation plates 6a and 6b are originally small, there may be cases where it is unnecessary to reduce the size of only the heat dissipation plate 6a. On the other hand, even for relatively large-sized control valves, since the heat dissipation plate 6a is often spaced apart from the flange portion 8, there may be cases where the necessity to reduce the size of only the heat dissipation plate 6a is low. For example, the structure of the present invention tends to exhibit particularly excellent effects in control valves with a size exceeding 1 inch and less than 4 inches. It should be noted that the other heat dissipation plates 6b do not all need to have the same outer diameter nor be arranged at equal intervals, as long as they satisfy the aforementioned conditions. The number of the other heat dissipation plates 6b is about 1 to 10, and their respective outer diameters and intervals can be experimentally determined so that the temperature at the installation portion of the packing 10 reaches a target temperature.

[0047] However, the intervals between the other heat dissipation plates 6b also affect the heat dissipation effect. Since the heat dissipation plates 6 are provided in the most effective number to obtain the maximum heat dissipation effect within a limited space volume, it is preferable that the other heat dissipation plates 6b are arranged at equal intervals. In addition, the bonnet 3 is a component to be subjected to treatments such as painting. From the viewpoint of improving painting workability, it is preferable that the intervals between the other heat dissipation plates 6b are as wide as possible, and for this purpose also, it is preferable that the other heat dissipation plates 6b are arranged at equal intervals. As described above, when comprehensively considering making the space volume where the heat dissipation plates 6 are provided as compact as possible, and taking into account overall factors such as heat dissipation performance and work efficiency during manufacturing of the control valve, it is preferable that the other heat dissipation plates 6b are arranged at equal intervals.

[0048] Furthermore, in the control valve of the present invention, it is preferable that the surface 15 of the heat dissipation plate 6 on the operation unit 5 side is inclined toward the body 1 side from the cylindrical portion 7 side toward the outer peripheral side. That is, it is preferable that the surface 13 of the heat dissipation plate 6 on the operation unit 5 side has a gradient inclined downward toward the outer periphery.

[0049] When the surface 15 of the heat dissipation plate 6 on the operation unit 5 side is inclined toward the body 1 side from the cylindrical portion 7 side toward the outer peripheral side as described above, water will not accumulate on the heat dissipation plate 6 due to rain when the control valve is installed outdoors, and the occurrence of corrosion and dirt such as moss is reduced. Here, it is preferable that the inclination is 2% or more in terms of hydraulic gradient.

[0050] It is preferable that the heat sink 6 has a sloped shape on the surface 15 on the operating section 5 side, and that it gradually thins from the cylindrical section 7 side towards the outer circumference. Since the cylindrical section 7 side is usually hotter than the outer circumference, by sloping the thickness of the heat sink 6 in this way, the spacing between the heat sinks widens from the hotter cylindrical section 7 side towards the outer circumference, thereby further enhancing the heat dissipation effect. Furthermore, when the heat sink 6 is integrally formed with the cylindrical section 7 by casting, providing such a thickness gradient also facilitates demolding, resulting in excellent manufacturing advantages.

[0051] Furthermore, it is preferable that the control valve of the present invention has a heat sink 6 that is integrally formed with the cylindrical portion 7. For example, the heat sink 6 can be manufactured integrally with the cylindrical portion 7 by casting.

[0052] Conventionally, when the bonnet 3 was connected to the body 1 with the heat sink 6 formed on the cylindrical portion 7, the heat sink 6 interfered with the attachment of the connecting member 9. However, as described above, the heat sink 6a closest to the flange portion 8 is positioned so as not to overlap with the connecting member 9 when viewed from above. This makes it easier to connect the bonnet 3 to the body 1 even when the heat sink 6 is integrally formed with the cylindrical portion 7. When the heat sink 6 is integrally formed with the cylindrical portion 7 in this way, improved heat conduction and enhanced heat dissipation can be expected.

[0053] As described above, in the present invention, for a heat sink 6 with a circular outer diameter, the heat sink 6a closest to the flange portion 8 has a smaller diameter than the other heat sinks 6b. However, the shape of the heat sink 6 is not necessarily limited to a perfect circle. The statement that the heat sink 6a has the smallest outer diameter of the other heat sinks 6b means that when the average value of the outer diameters is taken, the heat sink 6a closest to the other heat sinks 6b has a smaller outer diameter than the other heat sinks 6b. As long as this condition is met, even if the heat sink 6a partially protrudes outward from the heat sink 6b, it is still included in the present invention. For example, even if the heat sink 6a closest to the heat sink has a shape in which only the portion overlapping with the connecting member 9 is recessed inward, and the other portion has the same diameter as the other heat sinks 6b, it is still possible to obtain the effects of the present invention.

[0054] 1 Body 2 Valve body 3 Bonnet 4 Stem 5 Operating part 6 Heat sink 6a Nearest heat sink 6b Other heat sinks 7 Cylindrical part 8 Flange part 9 Connecting member 10 Inlet 11 Outlet 12 Packing 13 Seat ring 14 Seat retainer 15 Surface of heat sink on the operating part side 20 Control valve

Claims

1. A control valve comprising a body housing a valve body, an operating unit installed on the upper part of the body via a bonnet, a stem connecting the valve body and the operating unit and opening and closing the valve body by the operation of the operating unit, and a bonnet having a flange portion and a cylindrical portion, attached to the body by a connecting member at the flange portion, with the stem passing through the inside of the cylindrical portion, wherein a packing is arranged around the stem in the portion just before the stem is exposed to the outside of the bonnet, wherein the cylindrical portion of the bonnet is provided with a plurality of disc-shaped heat sinks, the heat sink closest to the flange portion having an outer diameter smaller than the outer diameter of the other heat sinks and being positioned so as not to overlap with the connecting member when viewed from above.

2. The control valve according to claim 1, wherein the heat sink closest to the flange portion has an outer diameter that fits inside the connecting member, and the other heat sinks have an outer diameter that fits inside the outer circumference of the flange portion.

3. The control valve according to claim 1 or 2, wherein the body is provided with a seat ring that opens and closes a flow path by moving a valve body toward and away from it, and a seat retainer interposed between the seat ring and the bonnet, which transmits the pressing force of the bonnet to the seat ring and fixes the seat ring to the body.

4. The control valve according to claim 1 or 2, wherein the surface of the heat sink on the operating part side is inclined toward the body side from the cylindrical part side toward the outer circumference side.

5. The control valve according to claim 1 or 2, wherein the heat sink is formed integrally with the cylindrical portion.

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