JP6979321B2 - Sealing device for rotary machine and rotating machine equipped with this sealing device - Google Patents

Description

The present disclosure relates to a sealing device for a rotating machine and a rotating machine provided with the sealing device.

As described in Patent Document 1, a rotating machine such as a steam turbine is provided with a sealing device for sealing between a turbine rotor and a ring-shaped ring member provided around the turbine rotor. ..

In a steam turbine provided with such a sealing device, in order to improve the performance of the steam turbine, it is necessary to reduce the steam leaking between the turbine rotor and the ring member, and for this purpose, during rated operation. It is necessary to reduce the clearance between the turbine rotor and the ring member in the above. From the start of the steam turbine until the rated operation is reached
Since the turbine rotor and ring members are deformed by the heat of steam compared to before the start of the steam turbine, the clearance may change from the start of the steam turbine to the time when the rated operation is reached. Therefore, it is necessary to set the setting clearance (initial clearance) so that the turbine rotor and the sealing device do not come into contact with each other in the state where the turbine rotor and the ring member are closest to each other (pinch point).

Japanese Unexamined Patent Publication No. 2009-293784

When the heat capacity of the ring member is larger than the heat capacity of the turbine rotor, the temperature of the ring member is less likely to rise than that of the turbine rotor when the steam turbine is started, so that the amount of deformation of the turbine rotor is larger than that of the ring member, and the turbine. The clearance between the rotor and the ring member tends to be small. Therefore, if the initial clearance is set so that the turbine rotor and the sealing device do not come into contact with each other at the pinch point, there is a problem that the clearance during rated operation becomes large and the performance of the steam turbine deteriorates. On the contrary, if the initial clearance is set so as to reduce the clearance during rated operation, there is a problem that the turbine rotor and the sealing device may come into contact with each other at the pinch point and the sealing device may be damaged.

In view of the above circumstances, it is an object of the present invention to provide a sealing device for a rotating machine capable of improving the performance of the rotating machine and a rotating machine provided with the sealing device.

(1) The sealing device for a rotating machine according to at least one embodiment of the present invention is
A ring-shaped ring member provided around a rotating body provided so as to be rotatable, and
A rotary machine sealing device comprising at least one sealing member held by the ring member and configured to seal a ring-shaped gap formed between the ring member and the rotating body. hand,
The ring member is inside the ring member.
An internal flow path communicating with the gap and
It is provided with at least one opening / closing mechanism for opening / closing the internal flow path according to at least one of the pressure or temperature of the fluid in contact with the ring member in the rotating machine.
When the at least one opening / closing mechanism opens the internal flow path, at least a part of the fluid flowing through the gap flows through the internal flow path.

According to the configuration of (1) above, since the fluid flows through the internal flow path by opening the internal flow path by at least one opening / closing mechanism, the temperature of the ring member also from the inside of the ring member due to the fluid flowing through the internal flow path. Increases, and the temperature rise of the ring member is promoted as compared with the case where the fluid in contact with the outside of the ring member in the rotating machine raises the temperature of the ring member. Then, the temperature difference between the ring member and the rotating body from the start of the rotating machine to the time when the rated operation is reached becomes small, and the difference in the amount of deformation of the ring member and the rotating body also becomes small. For this reason, the difference in the width (clearance) of the gap between the ring member and the rotating body at the pinch point and the rated operation is small, so the initial clearance can be set so that the clearance at the rated operation is as small as possible. Will be. As a result, the amount of fluid leaking from between the ring member and the rotating body during rated operation can be reduced, so that the performance of the rotating machine can be improved.

Further, according to the configuration of (1) above, since at least one opening / closing mechanism is provided inside the ring member, the entire sealing device can be made more compact than the configuration in which the opening / closing mechanism is provided outside the ring member. Can be done.

Further, according to the configuration of (1) above, at least one opening / closing mechanism opens / closes the internal flow path according to at least one of the pressure or temperature of the fluid in contact with the ring member in the rotating machine, so that the pressure or temperature of the fluid can be controlled. The internal flow path can be opened and closed at a more appropriate timing as compared with the form in which the opening / closing mechanism is operated according to the detected value of the sensor or the like to be detected.

(2) In some embodiments, in the configuration of (1) above,
The internal flow path is
The radial flow path portion extending in the radial direction of the rotating body and the
Includes an axial flow path portion extending in the axial direction of the rotating body.

According to the configuration of (2) above, since the internal flow path includes not only the radial flow path portion but also the axial flow path portion, the internal flow path includes the internal flow path as compared with the case where the internal flow path includes only the radial flow path portion. The heat transfer area of the heat exchange performed between the fluid flowing through the path and the ring member becomes large. Therefore, the temperature rise of the ring member is promoted as compared with the case where the internal flow path includes only the radial flow path portion, and as a result, the performance of the rotating machine can be further improved.

(3) In some embodiments, in the configuration of (1) or (2) above,
The internal flow path communicates with the gap between the sealing members adjacent to each other in the axial direction of the rotating body.
Compared to the number of seal members located downstream of the internal flow path located between the seal members in the flow direction of the fluid flowing through the gap, the internal flow path located between the seal members The number of the sealing members on the upstream side is smaller.

According to the configuration of (3) above, the fluid flows into the internal flow path as upstream as possible in the direction in which the fluid flows through the gap. Since the temperature and pressure of the fluid are higher on the upstream side, the temperature rise of the ring member is promoted as compared with the case where the fluid flows into the internal flow path on the downstream side, and as a result, the performance of the rotating machine can be further improved. ..

(4) In some embodiments, in any of the configurations (1) to (3) above,
The at least one opening / closing mechanism
At least one movable body configured to be able to open and close the internal flow path by moving across the internal flow path.
At least one fluid accommodating space formed inside the ring member so that the fluid in contact with the ring member can flow in, and the pressure of the fluid flowing into the fluid accommodating space moves the movable body. At least one fluid storage space that closes the internal flow path,
It comprises at least one elastic member configured to impart an elastic force to the at least one movable body to move the at least one movable body in a direction of opening the internal flow path.

According to the configuration of (4) above, at least one opening / closing mechanism opens / closes the internal fluid according to the pressure of the fluid in contact with the ring member in the rotating machine, so that it corresponds to the detection value of the sensor or the like that detects the pressure of the fluid. The internal flow path can be opened and closed at a more appropriate timing as compared with the form in which the opening / closing mechanism is operated.

(5) In some embodiments, in the configuration of (4) above,
A part of the fluid flowing through the internal flow path is configured to flow into the at least one fluid accommodating space.

According to the configuration of (5) above, the flow path through which the fluid flows into at least one fluid accommodating space becomes simpler than in the case where the fluid flows into at least one fluid accommodating space from other than the internal flow path. As a result, the configuration of the entire sealing device is simplified.

(6) In some embodiments, in any of the configurations (1) to (5) above,
The at least one opening / closing mechanism includes an elastic member made of a material having a coefficient of linear expansion higher than that of the material constituting the ring member.
The telescopic member is configured to be able to open and close the internal flow path by expanding and contracting so as to cross the internal flow path according to the temperature of the telescopic member.
The telescopic member is fixed inside the ring member only on the end side opposite to the end portion that crosses the internal flow path in the direction that crosses the internal flow path.

According to the configuration of (6) above, at least one opening / closing mechanism opens / closes the internal flow path according to the temperature of the fluid in contact with the ring member in the rotating machine. The internal flow path can be opened and closed at a more appropriate timing as compared with the form in which the opening / closing mechanism is operated accordingly.

(7) In some embodiments, in the configuration of (6) above,
Inside the ring member, a storage space configured to accommodate the telescopic member is formed.
The sealing device includes a lid member that closes the accommodation space from the outer peripheral side of the ring member.

According to the configuration of (7) above, the telescopic member can be easily assembled inside the ring member.

(8) The rotary machine according to at least one embodiment of the present invention is
A rotating body that is rotatably provided and
The sealing device according to any one of (1) to (7) above is provided.

According to the configuration of (8) above, since the fluid flows through the internal flow path by opening the internal flow path by at least one opening / closing mechanism, the temperature of the ring member also from the inside of the ring member due to the fluid flowing through the internal flow path. Increases, and the temperature rise of the ring member is promoted as compared with the case where the fluid in contact with the outside of the ring member in the rotating machine raises the temperature of the ring member. Then, the temperature difference between the ring member and the rotating body from the start of the rotating machine to the time when the rated operation is reached becomes small, and the difference in the amount of deformation of the ring member and the rotating body also becomes small. Therefore, since the difference in clearance between the ring member and the rotating body at the pinch point and the rated operation is small, it is possible to set the initial clearance so as to make the clearance at the rated operation as small as possible. As a result, the amount of fluid leaking from between the ring member and the rotating body during rated operation can be reduced, so that the performance of the rotating machine can be improved.

According to at least one embodiment of the present invention, since the fluid flows through the internal flow path by opening the internal flow path by at least one opening / closing mechanism, the fluid flowing through the internal flow path also causes the ring from the inside of the ring member. The temperature of the member rises, and the temperature rise of the ring member is promoted as compared with the case where the fluid in contact with the outside of the ring member in the rotating machine raises the temperature of the ring member. Then, the temperature difference between the ring member and the rotating body from the start of the rotating machine to the time when the rated operation is reached becomes small, and the difference in the amount of deformation of the ring member and the rotating body also becomes small. Therefore, since the difference in clearance between the ring member and the rotating body at the pinch point and the rated operation is small, it is possible to set the initial clearance so as to make the clearance at the rated operation as small as possible. As a result, the amount of fluid leaking from between the ring member and the rotating body during rated operation can be reduced, so that the performance of the rotating machine can be improved.

It is a schematic sectional drawing which shows the whole of the steam turbine which concerns on Embodiment 1 of this invention. It is a schematic sectional drawing which shows the sealing device of the steam turbine which concerns on Embodiment 1 of this invention. It is a schematic partial sectional view which shows the sealing device of the steam turbine which concerns on Embodiment 2 of this invention. FIG. 3 is a sectional view taken along line IV-IV of FIG. It is sectional drawing of the dummy ring provided with the sealing device which concerns on Embodiment 2 of this invention. It is sectional drawing for demonstrating the operation which the opening / closing mechanism of the sealing device which concerns on Embodiment 2 of this invention closes an internal flow path. It is a schematic partial sectional view which shows the modification of the sealing device of the steam turbine which concerns on Embodiment 2 of this invention.

Hereinafter, some embodiments of the present invention will be described with reference to the accompanying drawings. However, the scope of the present invention is not limited to the following embodiments. The dimensions, materials, shapes, relative arrangements, and the like of the components described in the following embodiments are not intended to limit the scope of the present invention to that, but are merely explanatory examples.

(Embodiment 1)
As shown in FIG. 1, the steam turbine 1 which is a rotary machine has an outer casing 2, a turbine rotor 3 which is a rotating body provided so as to penetrate the outer casing 2, and a turbine rotor 3 in the outer casing 2. A dummy ring 4 which is a ring-shaped ring member provided around the turbine rotor 3 and a ring-shaped wing ring 5 provided around the turbine rotor 3 in the outer casing 2 are provided.

As shown in FIG. 2, a ring-shaped gap 6 is formed between the turbine rotor 3 and the dummy ring 4. The steam turbine 1 (see FIG. 1) includes a sealing device 10 for sealing the gap 6. The sealing device 10 includes a plurality of sealing members 11 provided on the inner peripheral surface 4a of the dummy ring 4 facing the gap 6. The plurality of seal members 11 are provided along the axial direction of the turbine rotor 3, and each seal member 11 includes a plurality of seal segments 11a arranged along the circumferential direction of the turbine rotor 3.

The sealing device 10 also includes an internal flow path 12 formed inside the dummy ring 4. The internal flow path 12 has a radial flow path portion 12a having one end communicating with the gap 6 and extending the inside of the dummy ring 4 toward the radial outer side of the turbine rotor 3, and one end having the other end of the radial flow path portion 12a. Includes an axial flow path portion 12b that is connected to and extends along the axial direction of the turbine rotor 3 and the other end of which is open on the outer peripheral surface of the dummy ring 4. Although not depicted in FIG. 2, both the radial flow path portion 12a and the axial flow path portion 12b extend in the circumferential direction of the turbine rotor 3. The radial flow path portion 12a communicates with the gap 6 between the first sealing member 11 and the second sealing member 11 counting from the blade ring 5 (see FIG. 1) side.

The sealing device 10 is provided inside the dummy ring 4 and also includes an opening / closing mechanism 20 for opening / closing the internal flow path 12. The opening / closing mechanism 20 includes two movable bodies 21 and 22 configured to be able to open / close the internal flow path 12 by moving across the axial flow path portion 12b. Although not depicted in FIG. 2, each of the movable bodies 21 and 22 includes a plurality of movable segments 21a and 22a arranged along the circumferential direction of the turbine rotor 3. The movable segments 21a and 22a each have a plate-shaped pressure receiving portion 23, a plate-shaped seal portion 24 located parallel to the pressure receiving portion 23 at a distance from the pressure receiving portion 23, and the pressure receiving portion 23 and the seal portion 24, respectively. It includes a connecting portion 25 to be connected. The seal portion 24 is provided with a plurality of seal fins 26 extending in a direction crossing the axial flow path portion 12b. The pressure receiving portion 23, the sealing portion 24, and the connecting portion 25 may be formed as separate members, and they may be combined to form the movable segments 21a and 22a. The movable segments 21a and 22a may be formed by integrally forming the movable segments 21a and 22a.

Inside the dummy ring 4, two fluid accommodating spaces 30 and 31 communicating with the axial flow path portion 12b are formed through communication holes 32 and 33 formed so as to extend along the circumferential direction of the turbine rotor 3. Has been done. Although the fluid accommodating spaces 30 and 31 are not depicted in FIG. 2, they also extend along the circumferential direction of the turbine rotor 3 like the communication holes 32 and 33. The pressure receiving portions 23 of the movable segments 21a and 22a are arranged inside the fluid accommodating spaces 30 and 31, respectively, and the connecting portions 25 of the movable segments 21a and 22a are inserted into the communication holes 32 and 33, respectively. The seal portions 24 of the movable segments 21a and 22a are located in the axial flow path portion 12b.

Inside the fluid accommodating spaces 30 and 31, one end is connected to or abuts on the pressure receiving portion 23 of the movable segments 21a and 22a, and the other end is an elastic member connected to or abutting on the inner wall of the fluid accommodating spaces 30 and 31, respectively. 27 and 28 are provided. The springs 27 and 28 are configured to apply an elastic force that presses the pressure receiving portions 23 of the movable segments 21a and 22a toward the radial outer side of the turbine rotor 3 to the pressure receiving portions 23, respectively. As a result, when a force other than the elastic force due to the springs 27 and 28 does not act on the movable segments 21a and 22a, or an external force smaller than the elastic force acts (for example, steam turbine 1 (see FIG. 1)). At startup), the movable segments 21a and 22a are moved toward the radial outer side of the turbine rotor 3 by the elastic force, and each of the movable bodies 21 and 22 opens the internal flow path 12. On the other hand, although the detailed operation will be described later, when the pressure of steam is applied to the pressure receiving portion 23 and the force for pressing the pressure receiving portion 23 exceeds the elastic force due to the springs 27 and 28, the movable segments 21a and 22a of the turbine rotor 3 Moved inward in the radial direction, each of the movable bodies 21 and 22 closes the internal flow path 12.

Next, the operation of the sealing device according to the first embodiment of the present invention will be described.
As shown in FIG. 1, after the steam turbine 1 is started, steam flows into the vehicle interior 2. The steam that has flowed into the vehicle interior 2 flows into the blade ring 5, and the turbine rotor 3 rotates by working on the moving blades (not shown). Since the steam contacts both the turbine rotor 3 and the dummy ring 4 in the passenger compartment 2, the temperature of the turbine rotor 3 and the dummy ring 4 rises due to the heat of the steam. In the first embodiment, it is assumed that the heat capacity of the dummy ring 4 is larger than the heat capacity of a part of the turbine rotor 3 in the vicinity of the dummy ring 4.

As shown in FIG. 2, a ring-shaped gap 6 is formed between the turbine rotor 3 and the dummy ring 4. A fluid, that is, steam leaking from the blade ring 5 (see FIG. 1) side flows through the gap 6 in the direction of arrow A. Since the gap 6 is sealed by the sealing member 11, the amount of steam leaking through the gap 6 is suppressed, but if the width (clearance) of the gap 6 is too large, the sealing performance by the sealing member 11 is poor. When it becomes sufficient and the amount of leaking steam increases, the performance of the steam turbine 1 (see FIG. 1) deteriorates. Therefore, it is important to control the width of the gap 6 during the rated operation of the steam turbine 1.

As described above, the temperatures of the turbine rotor 3 and the dummy ring 4 rise until the steam turbine 1 starts and reaches the rated operation. When the temperatures of the turbine rotor 3 and the dummy ring 4 rise, each of them undergoes thermal deformation. If the temperatures of both rise in the same way, the thermal deformation of both becomes the same, so the fluctuation in the width of the gap 6 between the two is small, but the heat capacity of the dummy ring 4 is the turbine rotor near the dummy ring 4. If it is larger than the heat capacity of a part of 3, the deformation amount of the turbine rotor 3 is larger than the deformation amount of the dummy ring 4, so that the width of the gap 6 becomes smaller until the rated operation is reached. .. That is, there is a pinch point until the rated operation is reached. The width (initial clearance) of the gap 6 is set before the start of the steam turbine 1 so that the seal member 11 does not come into contact with the turbine rotor 3 at the pinch point.

However, when the rated operation is reached after the pinch point, the temperature difference between the turbine rotor 3 and the dummy ring 4 during the rated operation is smaller than the temperature difference between the two at the pinch point, so that the width of the gap 6 is large. This becomes larger than the size of the width of the gap 6 at the pinch point, which leads to deterioration of the sealing performance by the sealing member 11 and eventually deterioration of the performance of the steam turbine 1. Therefore, in the first embodiment, the sealing device 10 has the internal flow path 12 and the opening / closing mechanism 20 for opening and closing the internal flow path 12, thereby suppressing the possibility that the sealing member 11 comes into contact with the turbine rotor 3 at the pinch point. At the same time, the performance of the steam turbine 1 was improved by making the width of the gap 6 as small as possible during the rated operation. The operation of the sealing device 10 will be described below.

As described above, when the steam turbine 1 is started, each of the movable bodies 21 and 22 is in a state where the internal flow path 12 is open. Therefore, the steam flowing through the gap 6 in the direction of the arrow A enters the radial flow path portion 12a and flows through the axial flow path portion 12b rather than flowing through the gap 6 sealed by the sealing member 11 as it is. Then, it flows out from the dummy ring 4, that is, flows through the internal flow path 12. When the steam flows through the internal flow path 12, the temperature of the dummy ring 4 also rises from the inside of the dummy ring 4 due to the steam flowing through the internal flow path 12, and the steam in contact with the outside of the dummy ring 4 in the steam turbine 1 is a dummy. The temperature rise of the dummy ring 4 is promoted as compared with the case of raising the temperature of the ring 4.

Then, the temperature difference between the dummy ring 4 and the turbine rotor 3 from the start of the steam turbine 1 to the reaching the rated operation becomes small, and the difference in the amount of deformation between the dummy ring 4 and the turbine rotor 3 also becomes small. Therefore, since the width of the gap 6 at the pinch point and the rated operation is small, the width of the gap 6 is set before the start of the steam turbine 1 so that the width of the gap 6 at the rated operation can be made as small as possible. You will be able to set it. As a result, the amount of steam leaking through the gap 6 during rated operation can be reduced, so that the performance of the steam turbine 1 can be improved.

While the steam flows through the internal flow path 12, a part of the steam flows into each of the fluid accommodating spaces 30 and 31 through the communication holes 32 and 33 to increase the pressure of the fluid accommodating spaces 30 and 31. go. Since the steam pressure is low immediately after the steam turbine 1 is started, the force pressing the pressure receiving portions 23 of the movable segments 21a and 22a by the pressure of the fluid accommodating spaces 30 and 31 is smaller than the elastic force by the springs 27 and 28. , The movable segments 21a and 22a do not move. However, as the rated operation is approached, the pressure of the steam increases, and the pressures of the fluid accommodating spaces 30 and 31 also increase. Eventually, when the force pressing the pressure receiving portions 23 of the movable segments 21a and 22a due to the pressure of the fluid accommodating spaces 30 and 31 becomes larger than the elastic force of the springs 27 and 28, the movable segments 21a and 22a move in the radial direction of the turbine rotor 3. Moved inward, that is, across the axial flow path portion 12b, each of the movable bodies 21 and 22 closes the internal flow path 12. When the steam turbine 1 reaches the rated operation, each of the movable bodies 21 and 22 closes the internal flow path 12, so that steam does not flow through the internal flow path 12.

In this way, when the opening / closing mechanism 20 opens the internal flow path 12, steam flows through the internal flow path 12, so that the temperature of the dummy ring 4 also rises from the inside of the dummy ring 4 due to the steam flowing through the internal flow path 12. Then, the temperature rise of the dummy ring 4 is promoted as compared with the case where the steam in contact with the outside of the dummy ring 4 in the steam turbine 1 raises the temperature of the dummy ring 4. Then, the temperature difference between the dummy ring 4 and the turbine rotor 3 from the start of the steam turbine 1 to the reaching the rated operation becomes small, and the difference in the amount of deformation between the dummy ring 4 and the turbine rotor 3 also becomes small. Therefore, since the difference in the width of the gap 6 at the pinch point and the rated operation is small, it is possible to set the initial clearance so as to make the width of the gap 6 as small as possible during the rated operation. As a result, the amount of steam leaking from the gap 6 during rated operation can be reduced, so that the performance of the steam turbine 1 can be improved.

Further, in the first embodiment, since the opening / closing mechanism 20 opens / closes the internal flow path 12 according to the pressure of the steam flowing through the internal flow path 12, the opening / closing mechanism 20 opens / closes according to the detection value of the sensor or the like that detects the pressure of the steam. The internal flow path 12 can be opened and closed at a more appropriate timing as compared with the form in which 20 is operated.

In the first embodiment, the internal flow path 12 includes the radial flow path portion 12a and the axial flow path portion 12b, but the internal flow path portion 12 may include only the radial flow path portion 12a. However, since the internal flow path 12 includes not only the radial flow path portion 12a but also the axial flow path portion 12b, the internal flow path 12 includes the radial flow path portion 12a only, as compared with the case where the internal flow path portion 12 includes only the radial flow path portion 12a. The heat transfer area of the heat exchange performed between the steam flowing through the dummy ring 4 and the dummy ring 4 becomes large. Therefore, the temperature rise of the dummy ring 4 is promoted as compared with the case where the internal flow path 12 includes only the radial flow path portion 12a, and as a result, the performance of the steam turbine 1 can be further improved.

In the first embodiment, the radial flow path portion 12a communicates with the gap 6 between the first sealing member 11 and the second sealing member 11 counting from the blade ring 5 side, but is arbitrarily adjacent to each other. The seal members 11 may communicate with each other in the gap 6. However, since the temperature and pressure of the steam are higher toward the upstream side in the flow direction in which the steam flows through the gap 6, the temperature rise of the dummy ring 4 is promoted as compared with the case where the steam flows into the internal flow path 12 on the downstream side. As a result, the performance of the steam turbine 1 can be further improved. Therefore, it is preferable that the radial flow path portion 12a and the gap 6 communicate with each other on the upstream side as much as possible, and the seal member located on the downstream side of the radial flow path portion 12a located between the adjacent seal members 11 and 11. It is preferable that the number of the seal members 11 on the upstream side is smaller than the number of the radial flow path portions 12a located between the adjacent seal members 11 and 11.

In the first embodiment, six sealing members 11 are provided along the axial direction of the turbine rotor 3, but an arbitrary number of sealing members 11, that is, at least one sealing member 11 may be provided. Further, although the opening / closing mechanism 20 includes two movable bodies 21 and 22, any number of movable bodies, that is, at least one movable body may be included. Further, although the movable bodies 21 and 22 are provided so as to open and close the axial flow path portion 12b, they may be provided so as to open and close the radial flow path portion 12a.

In the first embodiment, the steam flowing into the fluid accommodating spaces 30 and 31 is the steam flowing through the internal flow path 12, but the present invention is not limited to this form. A flow path in which the steam in contact with the dummy ring 4 flows into the fluid accommodating spaces 30 and 31 other than the steam flowing through the internal flow path 12 is formed in the dummy ring 4, and the steam other than the steam flowing through the internal flow path 12 is formed. It may flow into the fluid accommodating spaces 30 and 31. However, in the form in which the steam flowing through the internal flow path 12 flows into the fluid accommodating spaces 30 and 31, the flow path through which the steam flows into the fluid accommodating spaces 30 and 31 becomes simpler, so that the entire sealing device 10 is configured. Is simplified.

(Embodiment 2)
Next, the sealing device according to the second embodiment will be described. The sealing device according to the second embodiment is a modification of the first embodiment in which the internal flow path is opened and closed. In the second embodiment, the same reference numerals as those of the constituent requirements of the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 3, the opening / closing mechanism 20 has a storage space 41 formed so as to communicate with the radial flow path portion 12a inside the dummy ring 4 and extend in the axial direction of the turbine rotor 3, and a storage space 41. It includes a stretchable member 40 that is housed therein and is made of a material having a higher coefficient of linear expansion than the material constituting the dummy ring 4. The telescopic member 40 is accommodated in the accommodation space 41 so as to extend in a direction orthogonal to the axial direction of the radial flow path portion 12a. One end 40b side of the telescopic member 40 is fixed in the accommodation space 41 by an arbitrary method such as fastening with bolts or welding in the direction extending in the accommodation space 41, and the other end 40a becomes a free end. ing.

As shown in FIG. 4, the telescopic member 40 and the accommodation space 41 extend in the circumferential direction of the turbine rotor 3. The telescopic member 40 has a curved plate shape extending in the circumferential direction of the turbine rotor 3, and both ends 40c and 40d of the telescopic member 40 in the circumferential direction of the turbine rotor 3 are not fixed in the accommodation space 41 and are free ends. It has become. Further, the two facing surfaces 40e and 40f of the telescopic member 40 extending in the circumferential direction of the turbine rotor 3 are also not fixed in the accommodation space 41. Therefore, only the end portion 40b (see FIG. 3) of the telescopic member 40 is fixed in the accommodation space 41.

As shown in FIG. 5, the dummy ring 4 is configured by fixing two semi-body portions 3a and 3b divided into two in the vertical direction by bolts 7. A storage space 41 is formed in each of the semifield portions 3a and 3b, and the expansion / contraction member 40 is housed in each storage space 41. Other configurations are the same as those in the first embodiment.

Next, the operation of the sealing device according to the second embodiment of the present invention will be described. However, the principle of improving the performance of the steam turbine 1 by minimizing the width of the gap 6 during rated operation by circulating steam in the internal flow path 12 is the same as that of the first embodiment. Only the different operations, that is, the operations of opening and closing the internal flow path 12, will be described below.

As shown in FIG. 3, before the start of the steam turbine 1 (see FIG. 1), the end portion 40a of the telescopic member 40 is a connection portion between the radial flow path portion 12a and the accommodation space 41, or the accommodation space 41. It is located inside. When the steam turbine 1 is started, the temperature of the dummy ring 4 rises due to the steam flowing through the internal flow path 12 in the same operation as in the first embodiment. When the temperature of the dummy ring 4 rises, the temperature of the telescopic member 40 also rises due to heat conduction from the dummy ring 4. Further, the temperature of the expansion / contraction member 40 also rises when the steam flowing through the internal flow path 12 comes into contact with the vicinity of the end portion 40a of the expansion / contraction member 40.

When the temperature of the dummy ring 4 and the expansion / contraction member 40 rises, both are thermally deformed. However, since the expansion / contraction member 40 is made of a material having a higher linear expansion coefficient than the material constituting the dummy ring 4, the dummy ring 40 is formed. It deforms more than 4. Then, since the end 40b side of the telescopic member 40 is fixed in the axial direction connecting the end 40a and the end 40b, the end 40a side is deformed, that is, thermally expanded in the direction away from the end 40b. As a result, as shown in FIG. 6, the telescopic member 40 closes the radial flow path portion 12a by extending the end portion 40a side of the telescopic member 40 so as to cross the radial flow path portion 12a. As a result, steam does not flow through the internal flow path 12.

When the steam turbine 1 is stopped and the temperature of the telescopic member 40 drops, the telescopic member 40 is deformed so that the end portion 40a side contracts toward the accommodation space 41, so that the radial flow path portion 12a can be opened. ..

As described above, since the opening / closing mechanism 20 opens the internal flow path 12 to allow steam to flow through the internal flow path 12 from the start of the steam turbine 1 to the time when the rated operation is reached, the same as in the first embodiment. The effect of can be obtained. Further, since the opening / closing mechanism 20 opens / closes the internal flow path 12 according to the temperature of the steam in contact with the dummy ring 4 in the steam turbine 1, the opening / closing mechanism 20 is opened and closed according to the detection value of the sensor or the like that detects the temperature of the steam. The internal flow path 12 can be opened and closed at a more appropriate timing as compared with the operating form.

In the second embodiment, the opening / closing mechanism 20 is provided to open / close the radial flow path portion 12a, but may be provided to open / close the axial flow path portion 12b.

In the second embodiment, as shown in FIG. 7, the accommodation space 41 is configured to open with respect to the outer peripheral surface 4b of the dummy ring 4, and the accommodation space 41 is provided by the lid member 42 from the outer peripheral surface 4b side of the dummy ring 4. You may try to close the opening of. With this configuration, the telescopic member 40 can be easily assembled inside the dummy ring 4.

In each of the first and second embodiments, the opening / closing mechanism 20 includes only one of the movable bodies 21 and 22 or the telescopic member 40, but may include both. In this case, for example, the telescopic member 40 can be used to open and close the radial flow path portion 12a, and the movable bodies 21 and 22 can be used to open and close the axial flow path portion 12b.

In the first and second embodiments, the steam turbine 1 has been described as an example of the rotary machine, but the present invention is not limited to the steam turbine 1. Anything that needs to optimize the clearance between the rotating body and the stationary body, such as a gas turbine, may be used. Further, in the steam turbine 1, the ring member is the dummy ring 4, but it may be a blade ring, a ground, or the like.

1 Steam turbine (rotary machine)
2 Foreign car room 3 Turbine rotor (rotating body)
3a Semi-body part 3b Semi-body part 4 Dummy ring (ring member)
4a (dummy ring) inner peripheral surface 4b (dummy ring) outer peripheral surface 5 wing ring 6 gap (clearance)
7 Bolt 10 Sealing device 11 Sealing member 11a Sealing segment 12 Internal flow path 12a Axial flow path 12b Axial flow path 20 Opening and closing mechanism 21 Movable body 21a Movable segment 22 Movable body 22a Movable segment 23 Pressure receiving part 24 Sealing part 25 Connecting Part 26 Seal fin 27 Spring (elastic member)
28 Spring (elastic member)
30 Fluid storage space 31 Fluid storage space 32 Communication hole 33 Communication hole 40 Telescopic member 40a (stretchable member) end 40b (stretchable member) end 40c (stretchable member) end 40d (stretchable member) end 40e Surface 40f (of the telescopic member) 41 Surface (of the telescopic member) Containment space 42 Lid member

Claims (6)

A ring-shaped ring member provided around a rotating body provided so as to be rotatable, and
A rotary machine sealing device comprising at least one sealing member held by the ring member and configured to seal a ring-shaped gap formed between the ring member and the rotating body. hand,
The ring member is inside the ring member.
An internal flow path communicating with the gap and
It is provided with at least one opening / closing mechanism for opening / closing the internal flow path according to at least one of the pressure or temperature of the fluid in contact with the ring member in the rotating machine.
When the at least one opening / closing mechanism opens the internal flow path, at least a part of the fluid flowing through the gap flows through the internal flow path.
The at least one opening / closing mechanism
At least one movable body configured to be able to open and close the internal flow path by moving across the internal flow path.
At least one fluid accommodating space formed inside the ring member so that the fluid in contact with the ring member can flow in, and the pressure of the fluid flowing into the fluid accommodating space moves the movable body. At least one fluid storage space that closes the internal flow path,
A sealing device for a rotating machine, comprising at least one elastic member configured to impart an elastic force to the at least one movable body to move the at least one movable body in a direction of opening the internal flow path. The sealing device for a rotating machine according to claim 1 , wherein a part of the fluid flowing through the internal flow path flows into the at least one fluid accommodating space. A ring-shaped ring member provided around a rotating body provided so as to be rotatable, and
A rotary machine sealing device comprising at least one sealing member held by the ring member and configured to seal a ring-shaped gap formed between the ring member and the rotating body. hand,
The ring member is inside the ring member.
An internal flow path communicating with the gap and
It is provided with at least one opening / closing mechanism for opening / closing the internal flow path according to at least one of the pressure or temperature of the fluid in contact with the ring member in the rotating machine.
When the at least one opening / closing mechanism opens the internal flow path, at least a part of the fluid flowing through the gap flows through the internal flow path.
The at least one opening / closing mechanism includes an elastic member made of a material having a coefficient of linear expansion higher than that of the material constituting the ring member.
The telescopic member is configured to be able to open and close the internal flow path by expanding and contracting so as to cross the internal flow path according to the temperature of the telescopic member.
The telescopic member is a rotary machine sealing device in which only the end portion opposite to the end portion crossing the internal flow path in the direction crossing the internal flow path is fixed inside the ring member. Inside the ring member, a storage space configured to accommodate the telescopic member is formed.
The sealing device for a rotating machine according to claim 3 , wherein the sealing device includes a lid member that closes the accommodation space from the outer peripheral side of the ring member. The internal flow path is
The radial flow path portion extending in the radial direction of the rotating body and the
The sealing device for a rotating machine according to any one of claims 1 to 4 , which includes an axial flow path portion extending in the axial direction of the rotating body. A rotating body that is rotatably provided and
A rotary machine including the sealing device according to any one of claims 1 to 5.

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