TWI616583B - Turbine cooling device - Google Patents

Abstract

The turbine cooling device according to the embodiment includes a cooling air supply unit (51) and a control unit (52), and cools a steam turbine in which a turbine rotor (300) is housed inside a turbine casing (110). The cooling air supply unit (51) supplies cooling air to the inside of the turbine casing. The control unit (52) controls the operation of the cooling air supply unit during the turning operation. Here, the control unit (52) controls the operation of the cooling air supply unit so that the cooling air supply unit supplies cooling air at a predetermined flow rate. Thereafter, the control unit (52) measures the expansion difference between the turbine rotor (300) and the turbine casing (110), and measures the position of the steam passage in the turbine casing (110) through which the steam passes. At least one of the results obtained by the temperature difference between the inner peripheral surface of the steam chamber at the inlet and the outer peripheral surface of the steam chamber controls the operation of the cooling air supply unit.

Description

Turbine cooling device

An embodiment of the present invention relates to a turbine cooling device.

The turbine cooling device is used to forcibly cool the steam turbine during maintenance and the like, for example. The turbine cooling device is cooled by supplying cooling air to the inside of the turbine casing during a turning operation performed after stopping the normal operation of the steam turbine.

The turbine cooling device, for example, in a turbine casing including a dual structure of an inner casing and an outer casing, supplies cooling air to the space between the inner casing and the outer casing and the inner space of the inner casing, respectively. Here, for example, the flow rate of the cooling air is adjusted based on a measurement result such as a differential expansion between a turbine casing and a turbine rotor accommodated in the turbine casing. In terms of such inventions, there is a Japanese Patent Publication, Japanese Unexamined Patent Publication No. 6-117204 (hereinafter referred to as Patent Document 1).

However, in the conventional turbine cooling device, it is sometimes difficult to cool the steam turbine in a short time. Therefore, the above-mentioned expansion difference or the above-mentioned temperature difference may be in a state outside a predetermined range. As a result, an alarm may occur.

Therefore, the problem to be solved by the present invention is to provide a turbine cooling device that can easily cool a steam turbine in a short time.

The turbine cooling device according to the embodiment includes a cooling air supply unit and a control unit, and cools a steam turbine in which a turbine rotor is housed inside a turbine casing. The cooling air supply unit supplies cooling air to the inside of the turbine casing. The control unit controls the operation of the cooling air supply unit during the turning operation. Here, the control unit controls the operation of the cooling air supply unit so that the cooling air supply unit supplies the cooling air at a predetermined flow rate. After that, the control unit measures the result of measuring the expansion difference between the turbine rotor and the turbine casing, and measures the inner peripheral surface of the steam chamber at the inlet of the steam passage through which the steam flows in the turbine casing and the steam chamber At least one of the results obtained by the temperature difference of the outer peripheral surface controls the operation of the cooling air supply unit.

1‧‧‧Steam Turbine System

10‧‧‧ Steam Turbine

11‧‧‧High-pressure turbine

12‧‧‧ medium pressure turbine

13‧‧‧The first low-pressure turbine

14‧‧‧ 2nd low-pressure turbine

20‧‧‧Main steam stop valve

30‧‧‧Steam regulating valve

40‧‧‧Reheat steam combination valve

50‧‧‧Turbine cooling device

51‧‧‧Cooling air supply department

52‧‧‧Control Department

110‧‧‧Turbine casing

201‧‧‧ Internal case

202‧‧‧External case

211‧‧‧ Upper half of inner case

212‧‧‧The lower half of the inner case

221‧‧‧ Upper half of external case

222‧‧‧ Lower half of external case

250a‧‧‧The first tubular body

250b‧‧‧ 2nd tubular body

300‧‧‧Turbine rotor

500a, 500b‧‧‧ sleeve

511‧‧‧Air Supply Department

512‧‧‧ cooling air piping system

600‧‧‧ cooling air discharge pipe

[Fig. 1] Fig. 1 is a model diagram of a steam turbine system according to the first embodiment. intention.

[Fig. 2] Fig. 2 is a schematic cross-sectional view of a high-pressure turbine in the steam turbine system according to the first embodiment.

3 is a schematic view of a first tubular body in a steam turbine system according to the first embodiment.

[FIG. 4] FIG. 4 is a schematic flowchart showing an outline of the operation of the steam cooling system in the steam turbine system according to the first embodiment when the steam cooling device cools the steam turbine.

[Fig. 5] Fig. 5 is a model diagram of a steam turbine system according to a second embodiment.

6] Fig. 6 is a model diagram of a steam turbine system according to a third embodiment.

7 is a schematic cross-sectional view of a high-pressure turbine in a steam turbine system according to a third embodiment.

[FIG. 8] FIG. 8 is a schematic diagram of a cooling air discharge pipe and a first tubular body in the steam turbine system 1 according to the first embodiment.

An embodiment will be described with reference to the drawings.

<First Embodiment> [A] Composition

FIG. 1 is a model diagram of a steam turbine system 1 according to the first embodiment. In FIG. 1, a solid-line arrow indicates a passage for supplying cooling air to the steam turbine 10 as a cooling medium, and an operation for supplying the steam turbine 10 is performed. A part of the passage of the medium vapor is appropriately omitted.

As shown in FIG. 1, the steam turbine system 1 includes a steam turbine 10 and a turbine cooling device 50.

[A-1] Steam turbine 10

In the steam turbine system 1, the steam turbine 10 includes a high-pressure turbine 11 and an intermediate-pressure turbine 12, and a first low-pressure turbine 13 and a second low-pressure turbine 14.

[A-1-1] High-pressure turbine 11

Among the steam turbines 10, as shown in FIG. 1, the high-pressure turbine 11 includes steam introduction portions 111 a and 111 b and a steam discharge portion 112. In the high-pressure turbine 11, the steam introduction portions 111a and 111b are connected to the main steam pipes F30a and F30b. The steam exhaust section 112 is connected to the low-temperature reheat steam pipe F11.

During normal operation of the steam turbine 10, the steam generated in the superheater (not shown) of the boiler (not shown) in the high-pressure turbine 11 passes through the main steam stop valve 20 and the steam regulating valve 30 in sequence, and flows. It passes through the main steam pipes F30a and F30b and flows into the steam introduction parts 111a and 111b as an operating medium. Here, the steam diverges at the branching section J30b, flows through the main steam pipes F30a, F30b, and flows into each of the plurality of steam introduction sections 111a, 111b. Then, in the high-pressure turbine 11, after the steam performs work, it is discharged from the steam discharge section 112 to the low-temperature reheat steam pipe F11.

FIG. 2 is a schematic cross-sectional view of the high-pressure turbine 11 in the steam turbine system 1 according to the first embodiment. In FIG. 2, it is revealed that the horizontal direction (x direction, y direction) is parallel to the rotation axis AX (x direction) Direction) and a vertical plane (xz plane) defined by the vertical direction (z direction).

As shown in FIG. 2, the high-pressure turbine 11 includes a turbine casing 110 and a turbine rotor 300. The high-pressure turbine 11 is a multi-stage axial-flow turbine. Inside the turbine casing 110, a turbine stage 400 including a stator blade cascade 401 and a rotor blade cascade 402 is provided along the turbine casing. The rotation axis AX is in a plurality of arrays side by side. The steam in a plurality of turbine stages 400 expands to perform work, and the turbine rotor 300 rotates around the rotation axis AX. The high-pressure turbine 11 is a single-flow exhaust type, and is configured such that steam flows from the steam introduction portions 111 a and 111 b provided on one end side of the turbine rotor 300 toward the steam discharge portion 112 provided on the other end side and exhausts.

Among the high-pressure turbines 11, the turbine casing 110 has a double structure, for example, and includes an internal casing 201 and an external casing 202.

In the turbine casing 110, an internal casing 201 houses a part of the turbine rotor 300 inside. In addition, the inner casing 201 supports the stator blade series 401 on the inner peripheral surface. In the stator blade series 401, a plurality of stator blades are arranged at intervals in the circumferential direction of the turbine rotor 300. The inner case 201 includes an upper half 211 of the inner case and a lower half 212 of the inner case, and is configured by combining the two.

In the turbine casing 110, the outer casing 202 houses the inner casing 201 inside. The outer casing 202 includes an outer casing upper portion 221 and an outer casing lower portion 222 and is configured by combining the two.

In the turbine casing 110, the steam introduction portions 111a, 111b, The first steam inlets 201a and 201b and the second steam inlets 202a and 202b are included.

The first steam inlet portions 201a and 201b are openings that penetrate between the inside and outside of the inner casing 201 and are formed in each of the upper half 211 and the lower half 212 of the inner casing.

The second steam inlet portions 202 a and 202 b are openings that penetrate between the outside and the outside of the outer casing 202 and are formed in each of the outer casing upper portion 221 and the outer casing lower portion 222.

Each of the first steam inlet portions 201a and 201b and the second steam inlet portions 202a and 202b is provided so as to be aligned coaxially in the radial direction of the turbine rotor 300 with a gap therebetween. Each of the first steam inlet portions 201a and 201b and the second steam inlet portions 202a and 202b is a passage having a circular cross section, and is connected to each other through sleeves 500a and 500b.

In the turbine casing 110, the vapor discharge portion 112 is an opening that penetrates between the inside and the outside of the outer casing 202.

In the high-pressure turbine 11, the turbine rotor 300 is a cylindrical rod-shaped body (shaft rod), and is constituted by a working fluid F flowing in an axial direction parallel to the rotation axis AX together with a rotor blade series 402 provided in the turbine rotor 300. While spinning. Here, in the turbine rotor 300, the rotation axis AX extends in the horizontal direction (x direction) and penetrates the turbine casing 110. The turbine rotor 300 is rotatably supported by a bearing (not shown) in each of one end portion and the other end portion. The turbine rotor 300 supports a rotor blade series 402 on an outer peripheral surface. In the rotor blade series 402, a plurality of rotor blades are The turbine rotor 300 is arranged at intervals in the circumferential direction.

The high-pressure turbine 11 includes a first tubular body 250a and a second tubular body 250b in addition to the above. Each of the first tubular body 250 a and the second tubular body 250 b is a linear tubular body, and is provided in the turbine casing 110 so that the tube axis extends in the radial direction of the turbine rotor 300. Here, each of the first tubular body 250a and the second tubular body 250b is inserted into the through holes 113a and 113b formed in the outer casing 202 and the through holes 114a and 114b formed in the inner casing 201.

Specifically, the first tubular body 250a is, for example, a balance plug assembling tube to which a balance plug (not shown) is assembled. The first tubular body 250a is supported by each of the through-hole 113a formed in the upper half 221 of the outer casing and the through-hole 114a formed in the upper half 211 of the inner casing.

In contrast, the second tubular body 250b is a thermocouple protection tube that houses a thermocouple (not shown) in the inside. The second tubular body 250b is supported by each of the through-hole 113b formed in the lower half 222 of the outer casing and the through-hole 114b formed in the lower half 212 of the inner casing.

FIG. 3 is a schematic view of the first tubular body 250a in the steam turbine system 1 according to the first embodiment. FIG. 3 illustrates a case where the direction (x direction) parallel to the rotation axis AX is the line of sight.

As shown in FIG. 3, the first tubular body 250a is formed with a cooling air discharge port H250a. The cooling air discharge port H250a is formed in the first tubular body 250a and is parallel to the rotation axis AX (x square of the turbine rotor 300). To) through. There are a plurality of cooling air discharge ports H250a, and they are arranged side by side along the tube axis (z direction in FIG. 3) of the first tubular body 250a. Like the first tubular body 250a, the second tubular body 250b has a cooling air discharge port H250b (see FIG. 2).

The details will be described later, but when the steam turbine system 1 performs a turning operation, in the present embodiment, the high-pressure turbine 11 is cooled by supplying cooling air from a turbine cooling device 50 (see FIG. 1). Here, the supplied cooling air passes through the steam introduction portions 111 a and 111 b and flows into the inside of the internal casing 201. Then, the cooling air that has flowed in passes through the inside of the inner casing 201 and is then discharged from the vapor discharge portion 112 to the outside. In other words, the cooling air flows through the steam path of the turbine casing 110 of the high-pressure turbine 11, which serves as an operating medium, that is, steam.

In this embodiment, the cooling air supplied from the turbine cooling device 50 passes through the cooling air discharge port H250a formed in the first tubular body 250a and the cooling air discharge port H250b formed in the second tubular body 250b, and flows into A space between the inner case 201 and the outer case 202. Then, the cooling air flows through a space between the inner case 201 and the outer case 202 and is then discharged from the vapor discharge portion 112 to the outside. That is, the cooling air circulates in a space outside the steam passage among the interior of the turbine casing 110 constituting the high-pressure turbine 11.

The high-pressure turbine 11 is provided with an expansion difference measuring unit (not shown) for measuring the expansion difference between the turbine rotor 300 and the turbine casing 110 in addition to the above. The expansion difference measurement unit is, for example, a potentiometer, and is provided in the turbine casing 110. Differential measurement unit, For example, it is configured to detect the gap between the sensing target of the turbine rotor 300 and the expansion difference measurement unit, thereby measuring the expansion difference. The result of the differential expansion measured in the differential expansion measurement unit is output to the turbine cooling device 50 as the measured data D10.

In addition, the high-pressure turbine 11 is provided with a temperature difference measurement unit (not shown), which measures the inner peripheral surface of the steam chamber located at the inlet of the steam passage where the turbine stage is arranged, inside the inner casing 201 constituting the turbine casing 110. And the temperature difference between the outer peripheral surface of the steam chamber (the temperature difference of the metal outside the steam chamber). The temperature difference measuring unit is, for example, a temperature sensor including a thermocouple, and is housed in a second tubular body 250b which is a thermocouple protection tube. In the temperature difference measuring section (not shown), for example, a plurality of thermocouples are provided to detect the temperature of the inner peripheral surface of the inner casing 201 constituting the turbine casing 110, and to detect the temperature of the outer peripheral surface of the inner casing 201. The temperature is used to measure the temperature difference. The temperature difference measured by the temperature difference measuring unit is output to the turbine cooling device 50 as the measured data D10.

[A-1-2] Medium pressure turbine 12

Among the steam turbines 10, as shown in FIG. 1, the intermediate-pressure turbine 12 includes a steam introduction portion 121 and steam discharge portions 122 a and 122 b. In the medium-pressure turbine 12, the steam introduction part 121 is connected to a high-temperature reheat steam pipe F40, and the steam discharge parts 122a and 122b are connected to crossover pipes F12a and F12b.

During normal operation in the steam turbine 10, in the intermediate-pressure turbine 12, the steam discharged from the high-pressure turbine 11 passes through the reheated steam combination valve 40, flows through the high-temperature reheated steam pipe F40, and flows into the steam introduction section 121. From The steam discharged from the high-pressure turbine 11 is heated again in a reheater (not shown) of a boiler (not shown), and then flows into the intermediate-pressure turbine 12 as an operating medium. This steam is subjected to work in the medium-pressure turbine 12 and then discharged from the steam discharge portions 122a and 122b to the cross pipes F12a, F12b, and F12c.

As can be seen from FIG. 1, the medium-pressure turbine 12 is of a multi-flow exhaust type. In a direction parallel to the rotation axis of the turbine rotor (not shown), the steam flows from the steam introduction portion 121 provided in the central portion toward the steam provided on one end side. The exhaust portion 122a and the steam exhaust portion 122b provided on the other end side flow and exhaust.

Although not shown, the intermediate-pressure turbine 12 is a multi-stage axial-flow turbine like the high-pressure turbine 11. Inside the turbine casing (not shown), a plurality of turbine stages (not shown) are arranged in parallel along the rotation axis. group.

The turbine casing of the intermediate-pressure turbine 12 has a double structure, like the high-pressure turbine 12, and includes an internal casing (not shown) and an external casing (not shown). The inner casing houses the turbine rotor inside. The internal casing includes the upper half of the internal casing (omitted from the illustration) and the lower half of the internal casing (omitted from the illustration), and is composed of a combination of the two. The outer casing houses the inner casing inside. The external casing includes the upper half of the external casing (omitted from the illustration) and the lower half of the external casing (omitted from the illustration), and is configured by combining the two.

In the medium-pressure turbine 12, the steam introduction portion 121 is an opening that penetrates the lower half of the inner casing and the lower half of the outer casing, and is a passage for introducing steam into the inner casing. The steam exhausting portions 122a and 122b are openings for penetrating between the inside and the outside of the upper half of the outer casing. A path for exhausting the vapor flowing from the inside of the inner casing to the outside.

As shown in FIG. 1, the intermediate-pressure turbine 12 is provided with a plurality of through holes 123 a, 123 b, 124 a, and 124 b in addition to the above. The plurality of through holes 123a, 123b, 124a, and 124b are formed to penetrate the lower half of the external casing. Here, the plurality of through holes 123a, 123b, 124a, and 124b are arranged side by side at a distance from each other in a direction parallel to the rotation axis of the turbine rotor. That is, the plurality of through holes 123a, 124a are juxtaposed from the central portion toward one end side, and the plurality of through holes 123b, 124b are juxtaposed from the central portion toward the other end side.

Details will be described later. However, in the steam turbine system 1, when the rotary operation is performed, in the present embodiment, the intermediate-pressure turbine 12 is cooled by supplying cooling air from the turbine cooling device 50 like the high-pressure turbine 11. Here, the cooling air passes through the steam introduction part 121 and flows into the inside of the inner cabinet. Then, the cooling air that has flowed in passes through the inside of the inner casing, and is then discharged from the steam discharge portions 122 a and 122 b to the outside.

In this embodiment, the cooling air supplied from the turbine cooling device 50 passes through the plurality of through holes 123a, 123b, 124a, and 124b, and flows into the space between the inner casing and the outer casing. Then, the cooling air flows through the space between the inner case and the outer case, and is then discharged from the steam discharge portions 122a and 122b to the outside.

In addition, as in the case of the high-pressure turbine 11, the intermediate-pressure turbine 12 is provided with an expansion difference measuring unit (not shown) for measuring the expansion difference between the turbine rotor and the turbine casing in addition to the above. In addition, the medium-pressure turbine 12 is provided with a temperature difference measurement unit (not shown), and the measurement constitutes a turbine The temperature difference between the inside of the steam chamber located at the entrance of the steam passage through which the steam flows, and the outside of the steam chamber is inside the cabinet. The result of the difference in expansion between the turbine rotor 300 and the turbine casing 110 measured in the expansion difference measuring unit and the result of the difference in temperature between the inside and outside of the steam chamber measured in the temperature difference measuring unit are output to the turbine cooling The device 50 is used as the measured data D10.

[A-1-3] The first low-pressure turbine 13 and the second low-pressure turbine 14

Among the steam turbines 10, as shown in FIG. 1, the first low-pressure turbine 13 includes a steam introduction portion 131 and steam discharge portions 132 a and 132 b. In the first low-pressure turbine 13, the steam introduction portion 131 is connected to the cross pipe F12c, and the steam discharge portions 132a and 132b are connected to the piping portions F13a and F13b.

Like the first low-pressure turbine 13, the second low-pressure turbine 14 includes a steam introduction portion 141 and steam discharge portions 142a and 142b. In the second low-pressure turbine 14, the steam introduction part 141 is connected to the cross pipe F12a, and the steam discharge parts 142a and 142b are connected to the piping parts F14a and F14b.

During normal operation of the steam turbine 10, the steam discharged from the intermediate-pressure turbine 12 in the first low-pressure turbine 13 and the second low-pressure turbine 14 flows through the cross pipes F12a, F12b, and F12c, and flows into the steam introduction sections 131, 141. As a medium of action. Here, in the cross pipes F12a, F12b, and F12c, the steam discharged from the intermediate-pressure turbine 12 converges at the junction point J12a, diverges at the divergence point J12b, and flows into the steam introduction portion 131 of the first low-pressure turbine 13 and the second low pressure. Each of the steam introduction portions 141 of the turbine 14. The steam is discharged from the steam discharge portions 132a, 132b, 142a, and 142b after the work of the first low-pressure turbine 13 and the second low-pressure turbine 14 is performed. Out. The steam discharged from each of the first low-pressure turbine 13 and the second low-pressure turbine 14 flows into the dehydrator 60 and is condensed.

As can be seen from FIG. 1, each of the first low-pressure turbine 13 and the second low-pressure turbine 14 is a multi-flow exhaust type like the medium-pressure turbine 12. In the direction parallel to the rotation axis of the turbine rotor (not shown), The steam introduction portions 131 and 141 provided in the central portion flow toward the steam discharge portions 132a and 142a provided on one end side and the steam discharge portions 132b and 142b provided on the other end side to exhaust.

Although not shown in the drawings, each of the first low-pressure turbine 13 and the second low-pressure turbine 14 is a multi-stage axial flow turbine like the high-pressure turbine 11 and the intermediate-pressure turbine 12, and is inside a turbine casing (not shown). , A plurality of turbine stages (not shown) are arranged side by side along the rotation axis to form an array.

The details will be described later, but when the steam turbine system 1 performs a rotary operation, in the present embodiment, each of the first low-pressure turbine 13 and the second low-pressure turbine 14 is the same as the high-pressure turbine 11 and the medium-pressure turbine 12. The turbine cooling device 50 is supplied with cooling air and is cooled. Here, the cooling air flows into the turbine casing through the steam introduction portions 131 and 141. Then, the inflowing cooling air flows through the inside of the turbine casing, and is then discharged from the steam discharge portions 132a, 132b, 142a, and 142b to the outside.

[A-2] Turbine cooling device 50

In the steam turbine system 1, as shown in FIG. 1, a turbine cooling device 50 includes a cooling air supply unit 51 and a control unit 52 to cool the steam turbine 10.

[A-2-1] Cooling air supply unit 51

In the turbine cooling device 50, the cooling air supply unit 51 includes an air blowing unit 511 and a cooling air piping system 512. The cooling air supply unit 51 supplies the cooling air supplied from the air supply unit 511 to the inside of the turbine casing of the steam turbine 10 through the cooling air piping system 512 during the turning operation performed after the normal operation of the steam turbine is stopped. The steam turbine 10 is forcibly cooled.

In the present embodiment, the cooling air supply unit 51 supplies cooling air to the inside of the turbine casing 110 (see FIG. 2) of the high-pressure turbine 11. Here, the cooling air supply unit 51 supplies cooling air to the inside of the internal casing 201 of the high-pressure turbine 11 and supplies cooling air to a space between the internal casing 201 and the external casing 202.

The cooling air supply unit 51 supplies cooling air to the inside of a turbine casing 110 (not shown) of the intermediate-pressure turbine 12. Here, the cooling air supply unit 51 supplies cooling air to the inside of the inner casing (not shown) of the medium-pressure turbine 12, and supplies cooling air to the space between the inner casing and the outer case (not shown). .

The cooling air supply unit 51 supplies cooling air to the inside of a turbine casing (not shown) of the first low-pressure turbine 13 and supplies cooling air to the inside of a turbine casing (not shown) of the second low-pressure turbine 14. .

[A-2-1-1] Air supply unit 511

Among the cooling air supply units 51, the blower unit 511 includes, for example, a blower (not shown).

In the blower section 511, the air blown by the blower is sent to the cooling air piping system 512 as cooling air.

[A-2-1-2] Cooling air piping system 512

Among the cooling air supply sections 51, the cooling air piping system 512 includes a plurality of piping sections F51, F511 to F514, F521 to F525, F13a, F13b, F14a, F14b, and a plurality of manual valves V51, V511 to V514, V521 to V525. , V13a, V13b, V14a, V14b, and a plurality of automatic valves M51, M511, M521 ~ M523.

In the cooling air piping system 512, each of the plurality of piping sections F51, F511 to F514, F521 to F525, F13a, F13b, F14a, and F14b is a passage for cooling air to be sent by the air supply section 511. While posing.

One end of the piping section F51 (first piping section) is connected to the air supply section 511, and the other end is connected to the connection point J30a of the main steam pipe F30a. The piping portion F51 is provided with a plurality of connection points J51a to J51d in order from one end to the other end. The piping portion F51 is provided with an automatic valve M51 and a manual valve V51 in this order from the one end to the other end between the other end and the connection point J51d provided at the other end side.

One end of the piping section F511 (second piping section) is connected to a connection point J51d provided on the other end side of the piping section F51 (first piping section). The other end of the piping portion F511 is connected to the high-pressure turbine 11. 通 孔 113a. The piping portion F511 is provided with a connection point J511 between one end and the other end. The piping portion F511 is provided with an automatic valve M511 between one end and the connection point J511. A manual valve V511 is provided between the other end of the piping portion F511 and the connection point J511.

The piping section F512 (third piping section) has one end connected to a connection point J511 of the piping section F511 (second piping section). The other end of the piping portion F512 is connected to the through hole 113 b of the high-pressure turbine 11. The piping portion F512 is provided with a manual valve V512 between one end and the other end.

The piping portion F513 (the fourth piping portion) is connected at one end to a connection point J11 of the low-temperature reheat steam tube F11. The piping portion F513 is provided with a connection point J513 between one end and the other end. In the piping portion F513, a manual valve V513 is provided between one end and the other end. The manual valve V513 is closed.

The piping section F514 (the fifth piping section) has one end connected to the connection point J513 of the piping section F513 (the fourth piping section). The other end of the piping portion F514 is open to the outside. The piping portion F514 is provided with a plurality of connection points J514a to J514d in order from one end to the other end. The piping portion F514 is provided with a manual valve V514 between one end and a connection point J514a provided on the most end side.

The piping section F521 (sixth piping section) has one end connected to the piping section F51 (first piping section) and is provided at a second connection point J51c from the other end side. The other end of the piping portion F521 is connected to the connection point J40 of the high-temperature reheat steam pipe F40. The piping portion F51 is provided with an automatic valve M521 and a manual valve V521 in this order from one end to the other end from one end to the other end.

The piping section F522 (seventh piping section) has one end connected to the piping section F51 (first piping section) and is provided at a connection point J51b that is third from the other end side. The other end of the piping portion F522 is connected to the through-hole 124 a of the intermediate-pressure turbine 12. The piping part F522 is provided with a connection point J522 between one end and the other end. The piping portion F522 is provided with an automatic valve M522 between one end and the connection point J522. The piping portion F522 is provided with an automatic valve V522 between the other end and the connection point J522.

One end of the piping section F523 (the eighth piping section) is connected to the connection point J51a of the piping section F51 (the first piping section) provided on the most end side. The other end of the piping portion F523 is connected to the through-hole 123 a of the intermediate-pressure turbine 12. The piping portion F523 is provided with a connection point J523 between one end and the other end. In the piping portion F523, an automatic valve M523 is provided between one end and the connection point J523. A manual valve V523 is provided between the other end of the piping portion F523 and the connection point J523.

The piping section F524 (the 9th piping section) has one end connected to the connection point J522 of the piping section F522 (the 7th piping section). The other end of the piping portion F524 is connected to the through hole 124 b of the intermediate-pressure turbine 12. The piping portion F524 is provided with a manual valve V524 between one end and the other end.

The piping section F525 (the 10th piping section) has one end connected to the connection point J523 of the piping section F523 (the 8th piping section). The other end of the piping portion F525 is connected to the through-hole 123 b of the intermediate-pressure turbine 12. The piping portion F525 is provided with a manual valve V525 between one end and the other end.

The piping portion F13a (the 11th piping portion) has one end connected to the steam exhaust portion 132a of the first low-pressure turbine 13. The piping section F13a One end is connected to a connection point J514a provided on the most end side of the piping section F514 (the fifth piping section). The piping portion F13a is provided with a manual valve V13a between one end and the other end.

The piping portion F13b (the 12th piping portion) has one end connected to the steam exhaust portion 132b of the first low-pressure turbine 13. In addition, the other end of the piping portion F13b is connected to the piping portion F514 (the fifth piping portion) at a connection point J514b that is second from the one end side. The piping portion F13b is provided with a manual valve V13b between one end and the other end.

The piping portion F14a (13th piping portion) is connected at one end to the steam discharge portion 142a of the second low-pressure turbine 14. In addition, the other end of the piping portion F14a is connected to the piping portion F514 (the fifth piping portion) at a connection point J514c provided at the third from the one end side. The piping portion F14a is provided with a manual valve V14a between one end and the other end.

The piping portion F14b (14th piping portion) has one end connected to the steam discharge portion 142b of the second low-pressure turbine 14. Moreover, the other end of the piping part F14b is connected to the connection point J514d provided in the piping part F514 (5th piping part) at the other end side. The piping portion F14b is provided with a manual valve V14b between one end and the other end.

Details will be described later, but in the cooling air piping system 512, the piping portion F51 (the first cooling air supply portion) is used when cooling air is supplied to the inside of the inner casing 201 among the turbine casings 110 of the high-pressure turbine 11. The piping sections F511 and F512 (second cooling air supply section) are used when cooling air is supplied to a space between the inner casing 201 and the outer casing 202 among the turbine casings 110 of the high-pressure turbine 11.

In the cooling air piping system 512, the piping portion F521 (the first cooling air supply portion) is used when cooling air is supplied to the inside of the inner casing of the turbine casing of the intermediate-pressure turbine 12. The piping sections F522 to F525 (second cooling air supply section) are used when cooling air is supplied to the space between the inner casing and the outer casing among the pulley casings of the medium-pressure turbine 12.

In addition, although not shown, in the cooling air piping system 512, each of the automatic valves M51, M511, M521 to M523 is configured to receive the control signal CTL52 output from the control unit 52, and automatically respond to the control signal CTL52 Adjust the opening of the valve. For example, each of the automatic valves M51, M511, M521 to M523 includes an actuator, and the actuator changes the distance between the valve body and the valve seat in response to the control signal CTL52.

[A-2-1] Control section 52

In the turbine cooling device 50, the control unit 52 is configured to control the operation of the cooling air supply unit 51 during a turning operation performed after stopping the normal operation of the steam turbine. The control unit 52 includes a calculator (not shown) and a memory device (not shown), and the calculator performs calculation processing using a program stored in the memory device. Thereby, the control part 52 outputs the control signal CTL52 to each part of the cooling air supply part 51, and controls the operation of each part.

Specifically, the control unit 52 outputs a control signal CTL52 to the air blowing unit 511, thereby controlling the operation of the air blowing unit 511. In addition, the control unit 52 outputs a control signal CTL52 to the automatic valves M51, M511, M521 to M523 of the cooling air piping system 512, thereby controlling the automatic valves M51, M511, M521 ~ M523 operation.

As described above, the control unit 52 inputs the result of the expansion difference and the result of the temperature difference from the steam turbine 10 as the measured data D10. Then, the control unit 52 outputs the control signal CTL52 using the input measured data D10.

[B] Action

Hereinafter, an operation when the turbine cooling device 50 forcibly cools the steam turbine 10 during a turning operation performed after stopping the normal operation of the steam turbine 10 will be described.

When the forced cooling operation for forcibly cooling the steam turbine 10 is performed, in the turbine cooling device 50, the control unit 52 obtains a command to perform the forced cooling operation, and outputs a control signal CTL52 to the cooling air supply unit 51. Then, based on the control signal CTL52, the cooling air supply unit 51 supplies cooling air to the inside of the turbine casing of the steam turbine 10.

In the cooling air supply unit 51, the cooling air sent from the blowing unit 511 is supplied to the inside of the turbine casing of the steam turbine 10 through the cooling air piping system 512. In the cooling air piping system 512, when a plurality of manual valves V51, V511 to V512, V514, V521 to V525, V13a, V13b, V14a, and V14b are all opened, a plurality of automatic valves M51, M511, M521 to M523 The valve opening degree is adjusted according to the control signal CTL52, and the cooling air flows through a plurality of piping sections F51, F511 ~ F514, F521 ~ F525, F13a, F13b, F14a, F14b. Among the above, the piping sections F13a, F13b, F14a, and F14b will pass. A part of the cooling air flowing through the first low-pressure turbine 13 or the second low-pressure turbine 14 circulates. The rest of the air passes through the first low-pressure turbine 13 or the second low-pressure turbine 14 and then flows to the dehydrator 60 and is released to the outside through the vacuum breaking valve V60.

FIG. 4 is a schematic flowchart showing an outline of the operation when the turbine cooling device 50 cools the steam turbine 10 in the steam turbine system 1 according to the first embodiment.

[B-1] Step 1 (ST1)

As shown in FIG. 4, when performing a forced cooling operation for forcibly cooling the steam turbine 10, first, cooling air is supplied at a predetermined flow rate.

In this embodiment, the predetermined flow rate is a flow rate obtained by numerical calculation in advance, so that each part of the steam turbine 10 is in an optimal state. Specifically, the flow rate determined in advance is a flow rate obtained by numerical calculation, so that the turbine rotor (symbol 300, etc. in FIG. 2) and the turbine casing (symbol 110, etc. in FIG. 2) in the steam turbine 10 The difference between the expansion between the steam chamber 10 and the inside of the turbine casing (symbol 110 in FIG. 2) of the steam turbine 10 is a temperature difference between the inside of the steam chamber located at the entrance of the steam passage through which the steam flows and the outside of the steam chamber. Time becomes the setting range.

In this step, the control unit 52 controls the operation of the cooling air supply unit 51 so that the cooling air supply unit 51 supplies cooling air to the steam turbine 10 at a predetermined time (see FIG. 1). and also That is, in the cooling air supply unit 51, the control unit 52 adjusts the valve opening degree of each of the plurality of automatic valves M51, M511, M521 to M523, thereby distributing and supplying cooling air having a predetermined flow rate to the steam turbine 10 Of the Ministry.

In this embodiment, the turbine cooling device 50 supplies cooling air of a predetermined flow rate to the high-pressure turbine 11 to cool the high-pressure turbine 11.

In this case, the cooling air supplied from the cooling unit 511 in the cooling air supply unit 51 flows through the piping unit F51 of the cooling air piping system 512 and flows into the steam introduction unit 111a of the high-pressure turbine 11 through the main steam pipes F30a and F30b. , 111b. The cooling air flows into the steam introduction parts 111a and 111b through the automatic valve M51 at a predetermined flow rate (see FIG. 1). The cooling air that has flowed into the steam introduction portions 111a and 111b passes through the inside of the inner casing 201 among the turbine casings 110 and is then discharged from the steam discharge portion 112 to the outside (see FIG. 2). In other words, the cooling air having a predetermined flow rate is supplied to a steam passage in the turbine casing 110 of the high-pressure turbine 11, through which steam as an operating medium flows.

In addition, the cooling air sent from the air blowing section 511 flows through the plurality of piping sections F51, F511, and F512 of the cooling air piping system 512, and then flows into the high pressure turbine 11 through the through holes 113a and 113b formed in the high pressure turbine 11. The cooling air flows into the high-pressure turbine 11 through the through holes 113 a and 113 b at a predetermined flow rate through the automatic valve M511 (see FIG. 1). The through holes 113a and 113b of the high-pressure turbine 11 are provided for the first tubular body 250a and the second tubular body 250b. The cooling air passes through the cooling air discharge port H250a formed in the first tubular body 250a and the cooling air discharge port H250b formed in the second tubular body 250b, and flows into the space between the inner casing 201 and the outer casing 202 (see FIG. 2). Then, the cooling air flows through a space between the inner case 201 and the outer case 202 and is then discharged from the vapor discharge portion 112 to the outside. That is, the cooling air having a predetermined flow rate is supplied to a space located outside the steam passage among the interior of the turbine casing 110 constituting the high-pressure turbine 11.

The cooling air discharged from the steam discharge section 112 of the high-pressure turbine 11 flows through the low-temperature reheat steam pipe F11. A part of the cooling air flowing through the low-temperature reheat steam pipe F11 is released to the outside, and the other part flows to the piping section F513 at the connection point J11. The cooling air flowing through the piping section F513 flows to the piping section F514 at the connection point J513. The cooling air flowing through the piping portion F514 is released to the outside.

In addition to the above, in this embodiment, the turbine cooling device 50 supplies cooling air having a predetermined flow rate to the intermediate-pressure turbine 12 to cool the intermediate-pressure turbine 12. The cooling air supplied to the intermediate-pressure turbine 12 is discharged to each of the first low-pressure turbine 13 and the second low-pressure turbine 14, and the first low-pressure turbine 13 and the second low-pressure turbine 14 are cooled.

In this case, the cooling air supplied from the cooling unit 511 in the cooling air supply unit 51 flows through the plurality of piping units F51 and F521 of the cooling air piping system 512, and then flows into the intermediate-pressure turbine 12 through the high-temperature reheat steam pipe F40.的 空气 引出 121。 The steam introduction part 121. The cooling air flows into the steam introduction part 121 at a predetermined flow rate through the automatic valve M521 (see figure 1). Although not shown in the drawing, the cooling air flowing into the steam introduction part 121 flows through the inside of the inner case among the turbine cases, and is then discharged from the steam discharge parts 122 a and 122 b to the outside (see FIG. 1). That is, the cooling air having a predetermined flow rate is supplied to a steam passage in the turbine casing of the intermediate-pressure turbine 12 for the circulation of the steam, which is the working medium.

In addition, the cooling air supplied from the air supply portion 511 flows through the plurality of piping portions F51, F522 to F525 of the cooling air piping system 512, and then flows into the medium pressure through the through holes 123a, 124a, 123b, and 124b formed in the medium pressure turbine 12. The interior of the turbine 12. The cooling air flows through the through holes 123a, 124a, 123b, and 124b through the automatic valves M522 and M523 into the medium pressure turbine 12 at a predetermined flow rate (see FIG. 1). The cooling air that has flowed into the through holes 123a, 124a, 123b, and 124b flows into a space between the inner casing and the outer casing constituting the turbine casing, although the illustration is omitted (see FIG. 2). Then, the cooling air flows through the space between the inner case and the outer case, and is then discharged from the steam discharge portions 122a and 122b to the outside. That is, the cooling air having a predetermined flow rate is supplied to a space located outside the steam passage among the interiors of the turbine casings constituting the intermediate-pressure turbine 12.

The cooling air discharged from the steam discharge portions 122a and 122b of the intermediate-pressure turbine 12 flows through the cross pipes F12a, F12b, and F12c. The cooling air flowing through the cross pipes F12a, F12b, and F12c flows into each of the first low-pressure turbine 13 and the second low-pressure turbine 14. Then, the cooling air flows through the inside of each of the first low-pressure turbine 13 and the second low-pressure turbine 14, and then exits from the steam discharge portions 132a, 132b, and And the steam discharge portions 142 a and 142 b of the second low-pressure turbine 14 are discharged.

Part of the cooling air discharged from the steam discharge sections 132a and 132b of the first low-pressure turbine 13 flows through the piping sections F13a and F13b, and then flows into the piping section F514 at the connection points J514a and J514b. Similarly, a part of the cooling air discharged from the steam discharge sections 142a and 142b of the second low-pressure turbine 14 flows through the piping sections F14a and F14b, and then flows into the piping section F514 at the connection points J514c and J514d. Then, the cooling air flowing through the piping portion F514 is released to the outside.

[B-2] Step 2 (ST2)

Next, as shown in FIG. 4, the cooling air flow rate is adjusted in accordance with the measured data (ST2).

Here, the control unit 52 controls the cooling air supply unit 51 based on the result of measuring the expansion difference between the turbine rotor (symbol 300 and the like in FIG. 2) and the turbine casing (symbol 110 and the like in FIG. 2) in the steam turbine 10. Actions. Furthermore, based on the results obtained by measuring the temperature difference between the inside of the steam chamber located at the entrance of the steam passage through which the steam flows, among the inside of the turbine casing (symbol 110, etc. in FIG. 2) of the steam turbine 10, The control unit 52 controls the operation of the cooling air supply unit 51. For example, the control unit 52 controls the operation of the cooling air supply unit 51 using a lookup table obtained by correlating the expansion difference, the temperature difference, and the flow rate.

Specifically, when the turbine rotor 300 of the high-pressure turbine 11 is longer than the set range according to the measurement result of the expansion difference, the adjustment is performed. The opening degree of the automatic valve M511 is such that the flow rate of the cooling air flowing through the piping portion F511 is reduced. That is, the flow rate of the cooling air is adjusted so as to change from a state where the temperature of the turbine casing 110 is lower than a temperature of the turbine rotor 300 to a state where the temperatures of both are approaching.

As a result of the above expansion difference, when the turbine rotor 300 of the high-pressure turbine 11 is shorter than the set range, the opening degree of the automatic valve M51 is adjusted so that the flow rate of the cooling air flowing through the piping portion F51 is reduced. That is, the flow rate of the cooling air is adjusted so as to change from a state where the temperature of the turbine rotor 300 is lower than the temperature of the turbine casing 110 to a state where the temperatures of both are approaching.

As a result of the temperature difference, when the temperature of the inner peripheral surface is lower than the temperature of the outer peripheral surface, the opening degree of the automatic valve M51 is adjusted so that the flow rate of the cooling air flowing through the piping portion F51 is reduced. That is, the flow rate of the cooling air is adjusted so as to change from a state where the temperature of the turbine rotor 300 is lower than the temperature of the turbine casing 110 to a state where the temperatures of both are approaching.

Regarding the case of the medium-pressure turbine 12, the flow rate of the cooling air is adjusted like the case of the high-pressure turbine 11.

[C] Summary (action, effect, etc.)

As described above, in the present embodiment, the turbine cooling device 50 includes the cooling air supply unit 51 and the control unit 52 that controls the operation of the cooling air supply unit 51 during the turning operation. The control unit 52 controls the operation of the cooling air supply unit 51 in a first step (ST1) so that the cooling air The air supply unit 51 supplies cooling air at a predetermined flow rate. Therefore, in this embodiment, in the first step (ST1), each part of the steam turbine 10 is cooled and approaches the most suitable state.

Thereafter, in the present embodiment, in the second step (ST2), the control unit 52 measures the expansion difference between the turbine rotor (reference numeral 300, etc. in FIG. 2) and the turbine casing (reference numeral 110, etc. in FIG. 2). The results obtained and the results obtained by measuring the temperature difference between the inner peripheral surface of the steam chamber located at the entrance of the steam passage through which the steam flows in the turbine casing (reference numeral 110 in FIG. 2 and the like), The operation of the cooling air supply unit 51 is controlled. Therefore, in this embodiment, when the expansion difference and the temperature difference are not in a predetermined range in the first step, the expansion difference and the temperature difference can be set in advance in the second step. Range.

Therefore, in this embodiment, the steam turbine 10 can be cooled in a short time, and a state in which the expansion difference or the temperature difference falls within a predetermined range can be created. An alarm occurs when the expansion difference or the temperature difference is outside a predetermined range, but in this embodiment, it is possible to prevent the alarm from occurring.

The turbine cooling device 50 of this embodiment is configured such that cooling air flows in a space between the inner casing 201 and the outer casing 202 in parallel to the rotation axis AX of the turbine rotor 300. Specifically, as described above, the first tubular body 250a and the second tubular body 250b extend along the radial direction of the turbine rotor 300. The first tubular body 250a and the second tubular body 250b include cooling air discharge ports H250a, H250b that pass through so as to be parallel to the rotation axis AX of the turbine rotor 300, and cool the air. Air flows from the cooling air discharge ports H250a, H250b into the space between the inner casing 201 and the outer casing 202 (see FIG. 2). Therefore, this embodiment can reduce the temperature difference between the inside and outside of the inner casing 201, so that the problem of thermal stress of the inner casing 201 can be eliminated, and the steam turbine 10 can be efficiently cooled.

In addition, in this embodiment, the first tubular body 250a is, for example, a balance plug assembling tube to which a balance plug (not shown) is assembled. The second tubular body 250b is, for example, a thermocouple protection tube that houses a thermocouple (not shown) in the inside. The first tubular body 250a is formed with a cooling air discharge port H250a, and the second tubular body 250b is formed with a cooling air discharge port H250b. Therefore, in this embodiment, the supply of cooling air can be realized by simple processing.

[D] Modification

In the above-mentioned embodiment, the case where the expansion between the turbine rotor (reference numeral 300, etc. in FIG. 2) and the turbine casing (reference numeral 110, etc. in FIG. 2) is measured in the second step (ST2) has been described. The result obtained by measuring the difference in temperature between the inner peripheral surface of the steam chamber located at the entrance of the steam passage through which the steam flows in the turbine casing (reference numeral 110 in FIG. 2 and the like) and the outer peripheral surface of the steam chamber. Both sides control the operation of the cooling air supply unit 51, but it is not limited to this. It may be configured to control the operation of the cooling air supply unit 51 in response to at least one of the expansion difference and the temperature difference.

In the high-pressure turbine 11 according to the above-mentioned embodiment, a case has been described in which the space between the inner casing 201 and the outer casing 202 flows The cooling air does not converge with the cooling air flowing through the inside of the internal casing 201, but exhausts from the high-pressure turbine 11, but is not limited to this. The high-pressure turbine 11 may be configured such that the cooling air flowing through the space between the inner casing 201 and the outer casing 202 and the cooling air flowing through the inside of the inner casing 201 are merged and exhausted from the high-pressure turbine 11.

In the above-mentioned embodiment, the case was explained based on the temperature difference between the inner peripheral surface of the steam chamber located at the inlet where the steam passage of the turbine stage is located inside the turbine casing 110 and the outer peripheral surface of the steam chamber. The operation of the cooling air supply unit 51 is controlled, but it is not limited to this. It may be configured to control the operation of the cooling air supply unit 51 based on the temperature difference between the upper half casing and the lower half casing.

In the present embodiment described above, the case where the first tubular body 250a is a balance plug assembling tube and the second tubular body 250b is a thermocouple protection tube is not limited thereto. The first tubular body 250a may not be used as a balance plug assembling tube. Similarly, the second tubular body 250b may not be used as a thermocouple protection tube.

<Second Embodiment> [A] Composition

FIG. 5 is a model diagram of the steam turbine system 1 according to the second embodiment. In FIG. 5, as in FIG. 1, a path of supplying cooling air as a cooling medium to the steam turbine 10 is indicated by a solid line arrow.

As shown in FIG. 5, in the cooling air supply unit 51 of this embodiment, the cooling air piping system 512 is different from the first embodiment (see As shown in Fig. 1), a part of manual valves V51, V511, V512, V521, V522, V523, V524, and V525 are not provided. The number of automatic valves M51, M511, M512, and M521 to M525 is larger than that in the first embodiment (see FIG. 1). This embodiment is the same as the case of the first embodiment except for the above-mentioned points and related points. Therefore, in this embodiment, descriptions of the points that overlap with those in the above embodiment are omitted as appropriate.

In this embodiment, each of the piping sections F51, F511, F512, F521 to F525 connected to each of the plurality of supply ports for supplying cooling air in the steam turbine 10 is provided with automatic valves M51, M511, M512, M521 to M525 .

Specifically, the automatic valve M51 is provided between the other end (the main steam pipe F30a side) and the connection point J51d provided at the other end side in the piping part F51 (first piping part).

The automatic valve M511 is provided between the other end (the side of the through hole 113a of the high-pressure turbine 11) and the connection point J511 in the piping section F511 (second piping section).

The automatic valve M512 is provided between one end and the other end (the side of the through hole 113b of the high-pressure turbine 11) in the piping portion F512 (third piping portion).

The automatic valve M521 is provided between one end and the other end in the piping portion F521 (sixth piping portion).

The automatic valve M522 is provided at the other end (the side of the through-hole 124a of the intermediate-pressure turbine 12) in the piping section F522 (the seventh piping section). And connection point J522.

The automatic valve M523 is provided between the other end (the side of the through-hole 123a of the intermediate-pressure turbine 12) and the connection point J523 in the piping portion F523 (the eighth piping portion).

The automatic valve M524 is provided between the one end and the other end (the side of the through-hole 123b of the intermediate-pressure turbine 12) in the piping section F524 (the eighth piping section).

The automatic valve M525 is provided between one end and the other end (the side of the through-hole 124b of the intermediate-pressure turbine 12) in the piping portion F525 (the ninth piping portion).

[B] Action

In the present embodiment, when the forced cooling operation for forcibly cooling the steam turbine 10 is performed, as in the case of the first embodiment (see FIG. 4), first in the first step (ST1), a predetermined flow rate is set. Supply cooling air. Next, in the second step (ST2), the flow rate of the cooling air is adjusted in accordance with the measured data (ST2).

In the second step (ST2), when the turbine rotor 300 of the high-pressure turbine 11 is longer than the set range, as in the case of the first embodiment, the opening degrees of the automatic valves M511 and M512 are adjusted in accordance with the expansion expansion result. To reduce the flow of cooling air flowing through the piping section F511.

In contrast, when the turbine rotor 300 of the high-pressure turbine 11 is shorter than the set range according to the result of the expansion difference described above, the opening degree of the automatic valve M51 is adjusted so that the flow of the cooling air flowing through the piping portion F51 量 REDUCED.

As a result of the temperature difference, when the temperature of the inner peripheral surface is lower than the temperature of the outer peripheral surface, the opening degree of the automatic valve M51 is adjusted so that the flow rate of the cooling air flowing through the piping portion F51 is reduced.

Regarding the case of the medium-pressure turbine 12, the flow rate of the cooling air is adjusted like the case of the high-pressure turbine 11.

[C] Summary (action, effect, etc.)

In this embodiment, unlike the case of the first embodiment, a part of the manual valves V51, V511, V512, V521, V522, V523, V524, and V525 (see FIG. 1) are not provided, but an automatic valve M51, M511, M512, M521, M522, M523, M524, M525, so as to double as the function of this unset manual valve. Therefore, simplification of the device can be easily achieved.

In this embodiment, as described above, each of the piping sections F51, F511, F512, and F521 to F525 connected to each of the plurality of supply ports for supplying cooling air in the steam turbine 10 is provided with automatic valves M51, M511, and M512. , M521 ~ M525. Therefore, in this embodiment, cooling can be performed more efficiently.

<Third Embodiment> [A] Composition

FIG. 6 is a model diagram of a steam turbine system 1 according to a third embodiment. In FIG. 6, as in FIG. 1, the steam turbine is indicated by a solid line arrow. 10 A passage for supplying cooling air as a cooling medium.

FIG. 7 is a schematic cross-sectional view of a high-pressure turbine 11 in a steam turbine system 1 according to a third embodiment. In FIG. 7, like FIG. 2, the vertical plane (xz plane) defined by the direction (x direction) parallel to the rotation axis AX and the vertical direction (z direction) among the horizontal directions (x direction, y direction) is disclosed. section.

As shown in FIG. 6, the high-pressure turbine 11 of this embodiment is not provided with a through hole 113b (see FIG. 1). Moreover, the piping part F512 and the manual valve V512 are not provided (refer FIG. 1). As shown in FIG. 7, the second tubular body 250 b is not provided (see FIG. 2). In this embodiment, unlike the case of the first embodiment (see FIG. 2), the cooling air supply unit 51 is provided with a cooling air discharge pipe 600. This embodiment is the same as the case of the first embodiment except for the above-mentioned points and related points. Therefore, in this embodiment, descriptions of the points that overlap with those in the above embodiment are omitted as appropriate.

In this embodiment, as shown in FIG. 7, the cooling air discharge pipe 600 is provided inside the turbine casing 110 of the high-pressure turbine 11.

FIG. 8 is a schematic diagram of the cooling air discharge pipe 600 and the first tubular body 250a in the steam turbine system 1 according to the first embodiment. As shown in FIG. 3, FIG. 8 shows a case where the direction (x direction) parallel to the rotation axis AX is the line of sight.

As shown in FIG. 8, the cooling air discharge pipe 600 is provided inside the turbine casing 110 between the internal casing 201 and the external casing 202. Here, the cooling air discharge pipe 600 has a ring shape and is provided so as to surround the internal unit. The outer peripheral surface of the case 201.

As shown in FIG. 8, the cooling air discharge pipe 600 has a plurality of cooling air discharge ports H600 through which the cooling air is discharged. The plurality of cooling air discharge ports H600 are formed around the outer peripheral surface of the inner casing 201 so as to be aligned at equal intervals.

The cooling air discharge pipe 600 is connected to the lower end portion of the first tubular body 250a at an upper portion, and the cooling air flowing through the first tubular body 250a is discharged from a plurality of cooling air discharge ports H600. The cooling air released from each of the plurality of cooling air discharge ports flows into a space between the inner case 201 and the outer case 202.

[B] Summary (action, effect, etc.)

As described above, in the present embodiment, the cooling air discharge pipe 600 is provided. In the cooling air discharge pipe 600, a plurality of cooling air discharge ports H600 are formed around the outer peripheral surface of the inner casing 201 so as to be aligned at equal intervals. Therefore, in this embodiment, the cooling air can be uniformly supplied to the space between the inner case 201 and the outer case 202.

Therefore, in this embodiment, the steam turbine 10 can be cooled in a short time.

In particular, this embodiment is suitable for a case where the through-hole 113b cannot be provided in the high-pressure turbine 11 and it is difficult to provide the second tubular body 250b.

<Other>

Although several embodiments of the present invention have been described, these embodiments are provided as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and changes can be made without departing from the gist of the invention. These embodiments and modifications are included in the scope or gist of the invention, and are included in the invention described in the scope of patent application and its equivalent scope.

1‧‧‧Steam Turbine System

10‧‧‧ Steam Turbine

11‧‧‧High-pressure turbine

12‧‧‧ medium pressure turbine

13‧‧‧The first low-pressure turbine

14‧‧‧ 2nd low-pressure turbine

20‧‧‧Main steam stop valve

30‧‧‧Steam regulating valve

40‧‧‧Reheat steam combination valve

50‧‧‧Turbine cooling device

51‧‧‧Cooling air supply department

52‧‧‧Control Department

60‧‧‧ Rehydrator

111a, 111b‧‧‧‧Steam introduction unit

112‧‧‧Steam discharge section

113a, 113b‧‧‧through hole

121‧‧‧Steam introduction department

122a, 122b‧‧‧‧Steam discharge section

123a, 123b, 124a, 124b‧‧‧through holes

131‧‧‧Steam introduction unit

132a, 132b‧‧‧‧Vapor discharge section

141‧‧‧Steam introduction department

142a, 142b‧‧‧‧Vapor discharge section

511‧‧‧Air Supply Department

512‧‧‧ cooling air piping system

CTL52‧‧‧Control signal

D10‧‧‧Measured data

F11‧‧‧Low temperature reheat steam tube

F12a, F12b, F12c‧‧‧ Cross tube

F30a, F30b‧‧‧ main steam pipe

F40‧‧‧High temperature reheat steam tube

F51, F511 ~ F514, F521 ~ F525, F13a, F13b, F14a, F14b‧‧‧Piping Department

V51, V511 ~ V514, V521 ~ V525, V13a, V13b, V14a, V14b‧‧‧Manual valve

V60‧‧‧Vacuum Breaking Valve

J12a‧‧‧ Meeting Point

J12b‧‧‧ divergence

J30b‧‧‧Division

J11, J30a, J40, J51a ~ J51d, J511, J513, J514a ~ J514d, J522, J523‧‧‧ connection points

M51, M511, M521 ~ M523‧‧‧Automatic valve

Claims (6)

A turbine cooling device is a turbine cooling device for cooling a steam turbine in which a turbine rotor is housed inside a turbine casing, comprising a cooling air supply unit for supplying cooling air to the inside of the turbine casing; and The control unit controls the flow of the cooling air from the cooling air supply unit during a turning operation performed after stopping the normal operation of the turbine; the control unit controls the operation of the cooling air supply unit so that the cooling air is supplied The cooling air is supplied at a predetermined flow rate so that an expansion difference between the turbine rotor and the turbine casing, and an inner peripheral surface of a steam chamber in the turbine casing, which is located at an inlet of a steam passage through which steam flows. The temperature difference from the outer peripheral surface of the steam chamber becomes a set range within a predetermined time, and thereafter the cooling air from the cooling air supply unit is controlled based on the result obtained by measuring the expansion difference and the result obtained by measuring the temperature difference. flow. The turbine cooling device according to item 1 of the scope of the patent application, wherein the turbine casing has: an internal casing that accommodates the turbine rotor inside; and an external casing that accommodates the internal casing inside; the foregoing The cooling air supply unit includes a first cooling air supply unit, which is provided before supplying the inside of the inner casing. Said cooling air; and a second cooling air supply unit that supplies said cooling air to a space between said internal casing and said external casing; said control unit controls said first cooling air supply unit and said second cooling air supply The operation of the unit causes the first cooling air supply unit and the second cooling air supply unit to supply the cooling air at a predetermined flow rate, and then based on the results obtained by measuring the expansion difference and the results obtained by measuring the temperature difference. At least one of them controls the operations of the first cooling air supply unit and the second cooling air supply unit. The turbine cooling device according to item 2 of the scope of patent application, wherein the cooling air supplied by the second cooling air supply unit is parallel to the space between the inner casing and the outer casing. The rotating shaft of the turbine rotor circulates. The turbine cooling device according to item 3 of the scope of patent application, further comprising: a tubular body extending along a radial direction of the turbine rotor; the tubular body including cooling air passing through parallel to a rotation axis of the turbine rotor; At the outlet, the cooling air supplied by the second cooling air supply unit flows from the cooling air outlet to a space between the inner casing and the outer casing. The turbo cooling device according to item 4 of the scope of patent application, wherein the tubular body includes: a first tubular body; and The second tubular body; each of the first tubular body and the second tubular body is formed with the cooling air discharge port. The turbine cooling device according to item 3 of the scope of the patent application, further comprising: a cooling air discharge pipe provided to surround the outer peripheral surface of the inner casing, and the cooling air discharge pipe formed a plurality of cooling air discharge A plurality of cooling air discharge ports are arranged side by side at an equal interval around the outer peripheral surface of the inner casing, and the cooling air supplied by the second cooling air supply unit is from each of the plurality of cooling air discharge ports. Circulating toward the space between the inner case and the outer case.