JP7709876B2 - Valve mechanism - Google Patents

Description

This invention relates to a valve device installed in a high-temperature fluid supply passage.

For example, Patent Document 1 describes a valve device that is installed in a high-temperature fluid supply passage. This valve device is a gate valve with a cooling structure, and a valve element that opens and closes the flow passage is attached inside a housing consisting of a valve box and a bonnet (referred to as a cap section in Patent Document 1) installed on top of the valve box, so that the valve element can be raised and lowered freely. The bonnet serves as a storage space for the valve element when in the open position.

The valve body is made of two circular steel valve plates connected by a pair of spiral plates that form a cooling water flow path from the center to the outer periphery. An annular seat ring is attached by welding to the outer periphery of the connected valve plates.

The peripheral wall of the seat ring is provided with a water inlet and a water outlet for cooling water to be supplied to the cooling water flow path, and a pair of hollow valve stems are connected in parallel to the water inlet and the water outlet. A cooling water inlet and outlet are provided at the top of the valve stem. Cooling water is supplied from the inlet, passes through the inside of the valve stem, enters the spiral cooling water flow path inside the seat ring from the water inlet, passes through the center of the valve body, passes through the inside of the valve stem from the water outlet, and is discharged from the outlet. This allows the entire valve body to be cooled uniformly.

The valve device described in Patent Document 2 is also known. This valve device opens and closes a hot air pipeline leading to a blast furnace, and is provided with a valve plate that can be raised and lowered inside a housing consisting of a valve box and a bonnet, and an annular air cooling passage adjacent to the sealed valve seat with which the valve plate moves. The air cooling passage is connected to a cooling air source. Cooling air supplied from the cooling air source is supplied to the housing interior space through the air cooling passage and a cooling gap that opens into the sealed surface of the sealed valve seat.

In the closed valve state, the cooling gap of the sealed valve seat is closed by the valve plate. This stops the inflow of cooling air into the housing internal space, allowing the sealed valve seat to be cooled (see Patent Document 2, page 2, lines 1 to 8, bottom left). In the closed valve state, the valve body blocks the thermal fluid, so the need to cool the sealed valve seat is considered to be relatively low. On the other hand, in the open valve state, the valve plate is pulled up to the bonnet provided on the top of the valve box, allowing cooling air to flow from the cooling gap into the housing internal space. This cools not only the sealed valve seat but also the housing internal space (see Patent Document 2, page 2, lines 15 to 1, bottom left).

JP 2003-262286 A Japanese Patent Application Laid-Open No. 60-132191

In the valve device of Patent Document 2, when the valve is open, the valve body (valve plate) is separated from the sealed valve seat, opening the cooling gap and allowing cooling air to flow into the housing. At this time, the valve body is pulled up inside the bonnet (cover) provided on the top of the valve box, so the cooling air ejected from the cooling gap does not hit the valve body directly.

However, depending on the type of fluid handled in the hot air pipeline and the specifications of the facility, there is a demand to further improve the cooling effect on the valve disc. For this reason, there is a demand to cool the valve disc more efficiently in both the closed and open valve states.

The objective of this invention is to further improve the cooling performance of the valve body in a valve device installed in a high-temperature fluid supply passage.

To solve the above problems, the present invention employs a valve device including a housing provided in a fluid supply passage, a valve body provided in the housing for opening and closing the fluid supply passage, a refrigerant passage provided in the valve body through which a refrigerant supplied from outside the housing flows, a first cooling gas supply unit that supplies the cooling gas supplied from outside the housing into the housing through a first opening provided in a valve seat against which the peripheral edge of the valve body in a closed valve state abuts, and a second cooling gas supply unit that supplies the cooling gas supplied from outside the housing into the housing through a second opening facing the valve body with a gap in between in a closed valve state or an open valve state.

The valve element is supported by a valve rod, and the valve rod moves axially to one side to close the valve and to the other side to open the valve. The second opening can be configured to include a valve box side opening that faces the other end of the valve element with a gap in the closed state, and a bonnet side opening that faces the other end of the valve element with a gap in the open state.

The second cooling gas supply unit may be configured to have a chamber adjacent to the second opening that has a cross-section larger than the cross-sectional area of the second opening.

The first cooling gas supply unit and the second cooling gas supply unit may be configured to receive the cooling gas from a common gas supply source.

In each of these embodiments, the second opening may be configured to be located downstream of the fluid supply passage relative to the valve body.

A heat pipe is provided inside the valve body, and has the function of transferring heat absorbed in the high temperature portion to a low temperature portion that is lower in temperature than the high temperature portion, and a configuration can be adopted in which the low temperature portion of the heat pipe in the valve body in the closed state faces the second opening.

The valve body may also include a heat pipe that transfers heat absorbed in the high-temperature portion to a low-temperature portion that is lower in temperature than the high-temperature portion, and the low-temperature portion of the heat pipe in the valve body in the open state may face the second opening or be exposed to the outside of the housing.

This invention can further improve the cooling performance of the valve body in a valve device installed in a high-temperature fluid supply passage.

FIG. 1 is an enlarged longitudinal sectional view showing a main part of an embodiment of the present invention. FIG. FIG. 3 is a right side view of FIG. 2 (however, the valve body is shown in an open state). Schematic diagram showing the positional relationship between the valve body and the chamber Schematic diagram showing the operation when the valve is closed Schematic diagram showing the operation in the open valve state Schematic diagram showing a modified example

An embodiment of the present invention will be described with reference to Figures 1 to 7. In this embodiment, the configuration of the present invention will be described using as an example a valve device 1 provided in a pipeline 10 for supplying a hot fluid (hereinafter referred to as a fluid supply line 10) leading to a blast furnace.

The valve device 1 is configured as a gate valve in which a valve box 2 is provided in the middle of a fluid supply line 10 and a valve body 20 that can move back and forth within the valve box 2. The fluid supply line 10 is opened and closed by the valve body 20 moving back and forth within the valve box 2. A valve box valve seat 45 that comes into contact with and separates from a valve body valve seat portion 34 provided on the peripheral portion of the valve body 20 is provided on the upstream side of the valve body 20 within the valve box 2. The valve box valve seat 45 is provided only on the upstream side of the valve body 20. The valve body valve seat portion 34 on the valve body side and the valve box valve seat 45 on the valve box side (hereinafter simply referred to as the valve seat 45) are each provided in an annular shape and abut against each other over the entire circumference in the closed valve state.

A valve ring 27 that comes into contact with and separates from the guide ring 7 is provided on the periphery of the valve body 20. The guide ring 7 and the valve ring 27 are each provided in an annular shape. The guide ring 7 and the valve ring 27 are made of metal, just like the valve body valve seat portion 34 and the valve seat 45, and have a metal-to-metal structure in which the metals rub against each other in the closed valve state.

When the valve is closed, the peripheral portion of the valve body 20 is pressed against the valve seat 45 by the force from the downstream side where the pressure is relatively high. For this reason, a one-sided valve seat type in which the valve seat 45 is provided only on the upstream side can be adopted. In addition, when the valve body 20 opens and closes, the guide ring 7 and the valve body ring 27 rub against each other on the downstream surface of the valve body 20 where the valve seat 45 is not provided, so that the refractories 14 and 22 described below do not interfere with the operation of the valve body 20.

The inner surface of the fluid supply passage 10 in the valve box 2, except for the space into which the valve body 20 enters, is covered with refractories 13, 14 made of a material that can withstand high heat and has heat retention properties. Refractory material 13 is arranged on the inner surface of the flow passage 11 on the upstream side of the valve body 20, and refractory material 14 is arranged on the inner surface of the flow passage 12 on the downstream side. A recess 8 into which the valve body 20 enters is provided between the upstream flow passage 11 and the downstream flow passage 12. The inner surface of the recess 8 is covered with a similar refractory material 15. Reference numeral 9 in Figures 1 to 3 denotes a drain, and reference numeral 46 in Figures 2 and 3 denotes a drain valve.

The valve box 2 is provided at its upper part with a hollow mounting portion 3 that protrudes outward beyond the outer surface of the cylindrical body that constitutes the fluid supply passage 10. Furthermore, a lid member 4 is attached to the upper part of the mounting portion 3 via flanges 3a, 4a. The valve box 2 (including the mounting portion 3) and the lid member 4 constitute a housing H. The interior of the mounting portion 3 and the lid member 4 also function as a bonnet 5 that houses the valve body 20 in the open state, and the inner surfaces of the mounting portion 3 and the lid member 4 are also covered with a refractory material 16 similar to that of the inside of the fluid supply passage 10. Hereinafter, the valve box 2 and the lid member 4 will be collectively referred to as the housing H.

A valve stem 6 is attached to the valve element 20. The valve stem 6 extends upward inside the bonnet 5 and is pulled out of the housing H. The valve stem 6 is driven by a drive device to move back and forth in the axial direction of the valve stem 6, and the valve element 20 moves back and forth together with the valve stem 6 in the same direction. That is, the valve element 20 closes when the valve stem 6 moves to one side along the axial direction of the valve stem 6 (downward), and opens when the valve stem 6 moves to the other side along the axial direction of the valve stem 6 (upward).

The valve body 20 is provided with a refrigerant passage 32 through which the refrigerant supplied from outside the housing H flows. As shown in FIG. 1, the valve body 20 has two metal (steel) valve plates 24, 25, one on the front and one on the back, which sandwich the refrigerant passage 32 located in the center of the thickness direction. A heat pipe 23 is arranged on the outside of the downstream valve plate 25, and the outside of that is covered with a refractory material 22. The outside of the upstream valve plate 24 is also covered with a refractory material 21. An annular seat ring is attached to the outer periphery of the valve body 20 to form the valve body valve seat 34. The outer periphery of the seat ring is also covered with a refractory material 28 on the side facing the recess 8.

As shown in FIG. 1, a pair of spiral plates are arranged in the disk-shaped space between the valve plates 24, 25 and the seat ring, as shown in FIG. 2. The spiral plates form a single refrigerant passage 32 that runs from a supply port provided on the outer periphery of the valve plates 24, 25 to the center, and then from the center to a discharge port provided on the outer periphery.

A pair of refrigerant passages 31 provided in each of the two valve rods 6 are connected to the supply port and the discharge port, respectively. The pair of refrigerant passages 31 are connected to a refrigerant supply source (not shown). The refrigerant supplied from the refrigerant supply source passes through the refrigerant passage 31 inside one of the valve rods 6, enters the refrigerant passage 32 from the supply port, passes through the center of the valve body 20, and then returns to the refrigerant supply source from the discharge port through the refrigerant passage 31 inside the other valve rod 6, forming a refrigerant supply section 30. The valve body 20 is cooled by this refrigerant supply section 30. In this embodiment, air is used as the refrigerant handled by the refrigerant supply section 30, but it may be a refrigerant made of a gas other than air, or a refrigerant made of a liquid.

The valve device 1 also includes a first cooling gas supply unit 40 that supplies cooling gas from a gas supply source 54 provided outside the valve box 2 and the bonnet 5, i.e., outside the housing H, into the valve box 2 through a first opening (cooling gap) 44 provided in the valve seat 45. As shown in Figs. 1 to 3, the first cooling gas supply unit 40 includes a valve box outer annular passage 41 that is connected to the gas supply source 54 via a communication passage 53 and surrounds the fluid supply path 10, a valve box inner annular passage (air-cooled circulation annular pipe for the valve body) 43 formed in the valve seat 45, and a plurality of connecting passages 42 that extend radially and connect the valve box outer annular passage 41 and the valve box inner annular passage 43. The valve seat 45 is made of a hollow annular member, and its interior serves as a passage for the cooling gas.

In this way, by providing the first cooling gas supply unit 40 having the first opening 44, the metal surface of the valve seat 45 can be cooled more efficiently than with a simple circulation type cooling device that does not have the first opening 44.

The valve box outer annular passage 41 and the valve box inner annular passage 43 are both located on the upstream side of the housing H, and this upstream position is blocked from hot air by the valve seat 45 when the valve is closed. This reduces the thermal effects from the downstream side, which is at high temperature and pressure. In this embodiment, air is used as the cooling gas, but gases other than air may also be used.

Furthermore, the valve device 1 is provided with a second cooling gas supply unit 50 that supplies the cooling gas supplied from outside the housing H into the housing H through a second opening (cooling gap) 52 provided in the housing H. As shown in Figures 2 and 3, the second cooling gas supply unit 50 is provided with a chamber (air reservoir) 51 connected to a gas supply source 54 via a communication passage 53. The chamber 51 is made of a hollow member, and its inside is a reservoir for cooling gas having a cross-sectional area larger than the cross-sectional area of the second opening 52 that leads to the space in the housing H. In this embodiment, two chambers 51 are provided in the housing H along the opening and closing direction of the valve body 20. Here, the chamber 51 on one side (the lower side in this embodiment) along the axial direction of the valve rod 6 is referred to as the valve box side chamber 51a, and the chamber 51 on the other side (the upper side in this embodiment) along the axial direction of the valve rod 6 is referred to as the bonnet side chamber 51b. In addition, the second opening 52 of the valve box side chamber 51a is referred to as the valve box side opening 52a, and the second opening 52 of the bonnet side chamber 51b is referred to as the bonnet side opening 52b.

In the closed valve state shown in FIG. 1, the valve box side opening 52a faces the other end (peripheral part) of the valve body 20 with a gap. In the closed valve state, the valve body 20 becomes particularly hot due to the heat received from the thermal fluid, but at that time, since the upper part of the valve body 20 is inserted into the mounting part 3 outside the fluid supply path 10, the part that has entered the mounting part 3 can be cooled by the cooling air discharged from the valve box side opening 52a. In this closed valve state, the bonnet side opening 52b does not face the valve body 20, so the discharge of the cooling air from the bonnet side opening 52b does not have much effect on the cooling of the valve body 20. For this reason, the discharge of the cooling air from the bonnet side opening 52b in the closed valve state may be stopped by providing an opening/closing valve in the communication passage 53 leading to the bonnet side chamber 51b.

In addition, in the open valve state shown in FIG. 7, the bonnet side opening 52b faces the other end (peripheral edge) of the valve body 20 with a gap therebetween. This allows the end of the valve body 20 farther from the fluid supply path 10 to be cooled by the cooling air discharged from the bonnet side opening 52b. Note that by providing an opening/closing valve in the communication passage 53 leading to the valve box side chamber 51a, the discharge of cooling air from the valve box side opening 52a in the open valve state may be stopped.

Since both the valve box side opening 52a and the bonnet side opening 52b are located downstream of the fluid supply path 10 relative to the valve body 20, a higher cooling effect can be expected in an environment where the relatively downstream side of the front and back surfaces of the valve body 20 is the high temperature side.

In the above embodiment, the first cooling gas supply unit 40 and the second cooling gas supply unit 50 are configured to receive cooling gas from a common gas supply source 54, but they may be supplied with cooling gas from separate gas supply sources.

Furthermore, in this embodiment, the valve body 20 is provided with a heat pipe 23 that has the function of transferring heat absorbed in the high temperature portion to a low temperature portion that is lower in temperature than the high temperature portion. An example of the location of the heat pipe 23 is shown in Figure 4.

In general, a heat pipe is a container that contains a working fluid sealed inside and has a capillary structure inside it. When part of the container is heated and a high-temperature area is generated, the working fluid in that high-temperature area absorbs the heat and evaporates. The vapor moves toward the low-temperature area inside the same container, where it condenses and releases heat. The condensed working fluid returns to the high-temperature area due to capillary action. This process is repeated to transfer heat from the high-temperature area to the low-temperature area.

In the closed valve state, the part of the valve body 20 that is inserted into the fluid supply path 10 corresponds to the high temperature part of the heat pipe 23. In contrast, the upper part of the valve body 20, i.e., the part that is inserted into the mounting part 3 outside the fluid supply path 10, corresponds to the low temperature part of the heat pipe 23 that is relatively lower in temperature than the high temperature part because it is less affected by heat from the thermal fluid. Therefore, as shown in FIG. 5, the heat pipe 23 transfers heat in the direction of the arrow a from the high temperature part (lower part 23a) in the fluid supply path 10 to the low temperature part (upper part 23b) in the bonnet 5. This cools the valve body 20. Because the cooling is performed inside the bonnet 5, it does not affect the temperature of the thermal fluid in the fluid supply path 10.

In addition, in this closed valve state, the low-temperature portion (upper portion 23b) of the heat pipe 23 faces the valve box side opening 52a. Therefore, the heat moving from the high-temperature portion (lower portion 23a) toward the low-temperature portion (upper portion 23b) is quickly cooled by the cooling air (see arrow b) discharged from the valve box side opening 52a. This allows the low-temperature portion to continue discharging the heat moving from the high-temperature portion. At this time, the discharge of cooling air from the bonnet side opening 52b may be stopped.

In addition, in the open valve state, the heat pipe 23 in the valve body 20 is entirely housed within the attachment portion 3 and bonnet 5, which are outside the fluid supply path 10. In this case, too, the lower portion 23a of the valve body 20, which is closer to the fluid supply path 10, corresponds to the high temperature portion. In contrast, the upper portion 23b of the valve body 20 corresponds to the low temperature portion, which is relatively lower in temperature than the high temperature portion, because it is farther from the thermal fluid in the fluid supply path 10. For this reason, as shown in FIG. 6, the heat pipe 23 transfers heat in the direction of arrow a, from the lower portion 23a to the upper portion 23b of the valve body 20.

In addition, in this open state, the low-temperature portion (upper portion 23b) of the heat pipe 23 faces the bonnet side opening 52b. Therefore, the heat moving from the high-temperature portion (lower portion 23a) toward the low-temperature portion (upper portion 23b) is quickly cooled by the cooling air (see arrow c) discharged from the bonnet side opening 52b. This allows the low-temperature portion to continue discharging the heat moving from the high-temperature portion. At this time, the discharge of cooling air from the valve box side opening 52a may be stopped.

Figure 7 shows a modified example of this embodiment. In this example, in the open state, the upper end of the heat pipe 23 in the valve body 20 is exposed to the atmosphere outside the bonnet 5 through a through hole provided in the upper part of the bonnet 5. Therefore, the lower part 23a of the valve body 20, which is closer to the fluid supply path 10, corresponds to the high temperature part, and the upper part 23b of the valve body 20 corresponds to the low temperature part, which is cooled by the atmosphere at the position indicated by the arrow d and is relatively lower in temperature than the high temperature part. Therefore, it is possible to ensure a large temperature difference between the high temperature part and the low temperature part, so that the cooling effect is higher. In this case, the bonnet side opening 52b and the bonnet side chamber 51b may be omitted. In addition, it is desirable to block the through hole so that the space inside the bonnet 5 does not communicate with the atmosphere even when the valve body 20 transitions to the closed state.

The installation of the heat pipe 23 is optional, so if the cooling function of the valve body 20 by the refrigerant supply unit 30, the first cooling gas supply unit 40, and the second cooling gas supply unit 50 is sufficient, its installation can be omitted.

The valve device 1 of the present invention can be applied to various fluid supply passages 10 that handle high-temperature thermal fluids. For example, the valve device 1 of the present invention can be applied to a burner shutoff valve provided in a fluid supply passage 10 that connects a hot stove that supplies hot air to a blast furnace and a burner that is its heat source, as well as a hot air valve provided in a fluid supply passage 10 that connects a hot stove and a blast furnace.

1 Valve device 2 Valve box 5 Bonnet 10 Fluid supply path (hot air pipe)
20 Valve body 23 Heat pipe 30 Coolant supply portion 32 Coolant passage 40 First cooling gas supply portion 44 First opening 45 Valve body valve seat (valve seat)
50: second cooling gas supply section 52: second opening 54: gas supply source

Claims (6)

A housing (H) provided in the fluid supply path (10);
a valve body (20) provided in the housing (H) for opening and closing the fluid supply passage (10);
a refrigerant passage (32) provided in the valve body (20) through which a refrigerant supplied from outside the housing (H) flows;
a first cooling gas supply section (40) that supplies a cooling gas supplied from outside the housing (H) into the housing (H) through a first opening (44) provided in a valve seat (45) against which a peripheral portion of the valve body (20) in a closed state abuts;
a second cooling gas supply section (50) that supplies a cooling gas supplied from outside the housing (H) into the housing (H) through a second opening (52) that faces the valve body (20) with a gap therebetween when the valve body is in a closed or open state ;
The valve body (20) is supported by a valve stem (6), and the valve is closed when the valve stem (6) moves in one axial direction and opens when the valve stem (6) moves in the other axial direction.
The second opening (52) is a valve device comprising a valve box side opening (52a) facing the other end of the valve body (20) with a gap in between in a closed valve state, and a bonnet side opening (52b) facing the other end of the valve body (20) with a gap in between in an open valve state . 2. The valve arrangement of claim 1, wherein the second cooling gas supply (50) comprises a chamber (51) adjacent the second opening (52) having a cross-section larger than the cross-sectional area of the second opening ( 52 ). 3. The valve device according to claim 1, wherein the first cooling gas supply section (40) and the second cooling gas supply section (50) are supplied with the cooling gas from a common gas supply source (54). A housing (H) provided in the fluid supply path (10);
a valve body (20) provided in the housing (H) for opening and closing the fluid supply passage (10);
a refrigerant passage (32) provided in the valve body (20) through which a refrigerant supplied from outside the housing (H) flows;
a first cooling gas supply section (40) that supplies a cooling gas supplied from outside the housing (H) into the housing (H) through a first opening (44) provided in a valve seat (45) against which a peripheral portion of the valve body (20) in a closed state abuts;
a second cooling gas supply section (50) that supplies a cooling gas supplied from outside the housing (H) into the housing (H) through a second opening (52) that faces the valve body (20) with a gap therebetween when the valve body is in a closed or open state ;
The second opening (52) is disposed downstream of the fluid supply passage (10) relative to the valve body (20) . A housing (H) provided in the fluid supply path (10);
a valve body (20) provided in the housing (H) for opening and closing the fluid supply passage (10);
a refrigerant passage (32) provided in the valve body (20) through which a refrigerant supplied from outside the housing (H) flows;
a first cooling gas supply section (40) that supplies a cooling gas supplied from outside the housing (H) into the housing (H) through a first opening (44) provided in a valve seat (45) against which a peripheral portion of the valve body (20) in a closed state abuts;
a second cooling gas supply section (50) that supplies a cooling gas supplied from outside the housing (H) into the housing (H) through a second opening (52) that faces the valve body (20) with a gap therebetween when the valve body is in a closed or open state ;
A heat pipe (23) is provided in the valve body (20) and has a function of transferring heat absorbed in a high-temperature portion to a low-temperature portion having a lower temperature than the high-temperature portion,
The valve device , in which the low-temperature portion of the heat pipe (23) in the valve body (20) in a closed state faces the second opening (52) . A housing (H) provided in the fluid supply path (10);
a valve body (20) provided in the housing (H) for opening and closing the fluid supply passage (10);
a refrigerant passage (32) provided in the valve body (20) through which a refrigerant supplied from outside the housing (H) flows;
a first cooling gas supply section (40) that supplies a cooling gas supplied from outside the housing (H) into the housing (H) through a first opening (44) provided in a valve seat (45) against which a peripheral portion of the valve body (20) in a closed state abuts;
a second cooling gas supply section (50) that supplies a cooling gas supplied from outside the housing (H) into the housing (H) through a second opening (52) that faces the valve body (20) with a gap therebetween when the valve body is in a closed or open state ;
A heat pipe (23) is provided in the valve body (20) and has a function of transferring heat absorbed in a high-temperature portion to a low-temperature portion having a lower temperature than the high-temperature portion,
The valve device in which a low-temperature portion of the heat pipe (23) in the valve body (20) in an open state faces the second opening (52) or is exposed to the outside of the housing (H) .