JP2016125355A - Turbine cooling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily realize quick cooling of a steam turbine.SOLUTION: A turbine cooling device includes a cooling air supply section and a control section and cools a steam turbine where a turbine rotor is stored in a turbine casing. The cooling air supply section supplies cooling air to an interior of the turbine casing. The control section controls operation of the cooling air supply section during turning operation. The control section controls the operation of the cooling air supply section so that the same supplies the cooling air with a predetermined flow rate. Then, the control section controls the operation of the cooling air supply section on the basis of at least either a result of measuring an elongation difference between the turbine rotor and the turbine casing or the result of measuring a temperature difference between an inner face and an outer face of a steam chamber positioned at an entrance of a steam passage, in the turbine casing, where steam flows therein.SELECTED DRAWING: Figure 1

Description

  Embodiments described herein relate generally to a turbine cooling device.

  The turbine cooling device is used for forcibly cooling the steam turbine, for example, at the time of inspection or the like. The turbine cooling device performs cooling by supplying cooling air to the inside of the turbine casing in a turning operation performed after stopping the normal operation of the steam turbine.

  For example, in a turbine casing having a double structure including an inner casing and an outer casing, the turbine cooling device supplies cooling air to each of a space between the inner casing and the outer casing and an inner space of the inner casing. Here, for example, the flow rate of the cooling air is adjusted based on a measurement result such as a difference in elongation between the turbine casing and the turbine rotor accommodated in the turbine casing.

JP-A-6-117204

  However, in the conventional turbine cooling device, it may be difficult to cool the steam turbine in a short time. For this reason, the elongation difference and the temperature difference may be in a state outside the 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 realize cooling of a steam turbine in a short time.

  The turbine cooling device of the embodiment includes a cooling air supply unit and a control unit, and cools a steam turbine that houses a turbine rotor 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 measured the difference in elongation between the turbine rotor and the turbine casing, and the inner peripheral surface of the steam chamber located at the inlet of the steam flow path through which the steam flows in the turbine casing and the outer periphery of the steam chamber. The operation of the cooling air supply unit is controlled based on at least one of the results of measuring the temperature difference with the surface.

Drawing 1 is a figure showing typically the steam turbine system concerning a 1st embodiment. FIG. 2 is a cross-sectional view showing a high-pressure turbine in the steam turbine system according to the first embodiment. FIG. 3 is a diagram illustrating a first tubular body in the steam turbine system according to the first embodiment. FIG. 4 is a flowchart showing an outline of an operation when the turbine cooling device cools the steam turbine in the steam turbine system according to the first embodiment. FIG. 5 is a diagram schematically illustrating a steam turbine system according to the second embodiment. FIG. 6 is a diagram schematically illustrating a steam turbine system according to the third embodiment. FIG. 7 is a cross-sectional view showing a high-pressure turbine in the steam turbine system according to the third embodiment. FIG. 8 is a diagram illustrating a cooling air discharge pipe and a first tubular body in the steam turbine system 1 according to the first embodiment.

  Embodiments will be described with reference to the drawings.

<First Embodiment>
[A] Configuration FIG. 1 is a diagram schematically illustrating a steam turbine system 1 according to the first embodiment. In FIG. 1, the flow path of the cooling air supplied as a cooling medium to the steam turbine 10 is indicated by solid arrows, and a part of the flow path of the steam supplied as the working medium to the steam turbine 10 is omitted as appropriate. doing.

  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, an intermediate pressure turbine 12, 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, the high-pressure turbine 11 includes steam introduction portions 111 a and 111 b and a steam discharge portion 112 as shown in FIG. 1. In the high-pressure turbine 11, the steam introduction portions 111a and 111b are connected to main steam pipes F30a and F30b. The steam discharge part 112 is connected to the low temperature reheat steam pipe F11.

  When normal operation is performed in the steam turbine 10, the high-pressure turbine 11 causes the steam generated in the superheater (not shown) of the boiler (not shown) to sequentially turn the main steam stop valve 20 and the steam control valve 30. Through the main steam pipes F30a and F30b, and flows into the steam introducing portions 111a and 111b as a working medium. Here, the steam branches at the branch portion J30b, flows through the main steam pipes F30a and F30b, and flows into the plurality of steam introduction portions 111a and 111b, respectively. In the high-pressure turbine 11, the steam is discharged from the steam discharge unit 112 to the low-temperature reheat steam pipe F <b> 11 after performing work.

  FIG. 2 is a cross-sectional view showing the high-pressure turbine 11 in the steam turbine system 1 according to the first embodiment. FIG. 2 shows a cross section of a vertical plane (xz plane) defined by a direction (x direction) along the rotation axis AX in the horizontal direction (x direction, y direction) and a vertical direction (z direction). Yes.

  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 multistage axial turbine, and a plurality of turbine stages 400 including a stationary blade cascade 401 and a moving blade cascade 402 are arranged along the rotation axis AX in the turbine casing 110. As the steam expands and performs work in the turbine stage 400, the turbine rotor 300 rotates about the rotation axis AX. The high-pressure turbine 11 is a single-flow exhaust type, and steam flows from the steam introduction portions 111a and 111b provided on one end side of the turbine rotor 300 toward the steam discharge portion 112 provided on the other end side. It is configured to be.

  Of the high-pressure turbine 11, the turbine casing 110 has a double structure, for example, and includes an inner casing 201 and an outer casing 202.

  In the turbine casing 110, the inner casing 201 accommodates a part of the turbine rotor 300 therein. At the same time, the inner casing 201 supports the stationary blade cascade 401 on the inner peripheral surface. In the stationary blade cascade 401, a plurality of stationary blades are arranged at intervals in the circumferential direction of the turbine rotor 300. The inner casing 201 includes an inner casing upper half 211 and an inner casing lower half 212, and is configured by combining the two.

  In the turbine casing 110, the outer casing 202 accommodates the inner casing 201 therein. The outer casing 202 includes an outer casing upper half 221 and an outer casing lower half 222, and is configured by combining both.

  In the turbine casing 110, the steam introduction portions 111a and 111b include first steam inlet portions 201a and 201b and second steam inlet portions 202a and 202b.

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

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

  The first steam inlet portions 201a and 201b and the second steam inlet portions 202a and 202b are provided so as to be arranged coaxially in the radial direction of the turbine rotor 300, and a gap is interposed between them. . The first steam inlet portions 201a and 201b and the second steam inlet portions 202a and 202b are flow paths having a circular cross section, and are connected to each other via sleeves 500a and 500b.

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

  Among the high-pressure turbines 11, the turbine rotor 300 is a cylindrical rod-like body (shaft), and together with the moving blade cascade 402 installed in the turbine rotor 300, the working fluid F that flows in the axial direction along the rotation axis AX. It is configured to rotate. 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 at one end and the other end by a bearing (not shown). The turbine rotor 300 supports the rotor blade cascade 402 on the outer peripheral surface. In the moving blade cascade 402, a plurality of moving blades are arranged at intervals in the circumferential direction of the turbine rotor 300.

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

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

  On the other hand, the 2nd tubular body 250b is a thermocouple protection cylinder which accommodates a thermocouple (illustration omitted) inside. The second tubular body 250b is supported by being inserted into each of a through hole 113b formed in the lower half portion 222 of the outer casing and a through hole 114b formed in the lower half portion 212 of the inner casing.

  FIG. 3 is a diagram showing the first tubular body 250a in the steam turbine system 1 according to the first embodiment. FIG. 3 shows a state in which the direction (x direction) along the rotation axis AX is a line of sight.

  As shown in FIG. 3, the first tubular body 250a has a cooling air discharge port H250a. The cooling air discharge port H250a is formed in the first tubular body 250a so as to penetrate along the rotation axis AX (x direction) of the turbine rotor 300. A plurality of cooling air discharge ports H250a are arranged along the tube axis (z direction in FIG. 3) of the first tubular body 250a. Similarly to the first tubular body 250a, the second tubular body 250b also has a cooling air discharge port H250b (see FIG. 2).

  Although details will be described later, when the turning operation is performed in the steam turbine system 1, in the present embodiment, the high-pressure turbine 11 is cooled by being supplied with cooling air from the turbine cooling device 50 (see FIG. 1). Here, the supplied cooling air flows into the inner casing 201 through the steam inlets 111a and 111b. The inflowing cooling air flows through the inner casing 201 and is then discharged from the steam discharge unit 112 to the outside. That is, the cooling air flows through the steam flow path in which the steam flows as the working medium in the turbine casing 110 of the high-pressure turbine 11.

  At the same time, in the present embodiment, the cooling air supplied from the turbine cooling device 50 is the cooling air discharge port H250a formed in the first tubular body 250a and the cooling air formed in the second tubular body 250b. It flows into the space between the inner casing 201 and the outer casing 202 via the discharge port H250b. Then, the cooling air flows through the space between the inner casing 201 and the outer casing 202, and then is discharged from the steam discharge unit 112 to the outside. That is, the cooling air flows in a space located outside the steam flow path in the turbine casing 110 constituting the high-pressure turbine 11.

  In addition to the above, the high-pressure turbine 11 is provided with an elongation difference measuring unit (not shown) that measures an elongation difference between the turbine rotor 300 and the turbine casing 110. The differential elongation measuring unit is, for example, a potentiometer and is installed in the turbine casing 110. The differential elongation measuring unit is configured to measure the differential elongation by detecting a gap between the sensor target of the turbine rotor 300 and the differential elongation measuring unit, for example. The result of the elongation difference measured by the elongation difference measuring unit is output to the turbine cooling device 50 as measured data D10.

  Further, the high pressure turbine 11 has a temperature between the inner peripheral surface of the steam chamber located at the inlet of the steam flow path in which the turbine stage is arranged inside the inner casing 201 constituting the turbine casing 110 and the outer peripheral surface of the steam chamber. A temperature difference measuring unit (not shown) for measuring the difference (metal temperature difference between the outer surfaces of the steam chamber) is installed. The temperature difference measurement unit is, for example, a temperature sensor including a thermocouple, and is accommodated in the second tubular body 250b that is a thermocouple protection cylinder. In the temperature difference measuring unit (not shown), the thermocouple detects, for example, the temperature of the inner peripheral surface of the inner casing 201 that constitutes the turbine casing 110 and the temperature of the outer peripheral surface of the inner casing 201, A plurality are installed so as to measure the temperature difference. The result of the temperature difference measured by the temperature difference measuring unit is output to the turbine cooling device 50 as measured data D10.

[A-1-2] Medium pressure turbine 12
Among the steam turbines 10, the intermediate pressure turbine 12 includes a steam introduction part 121 and steam discharge parts 122 a and 122 b as shown in FIG. 1. In the intermediate pressure turbine 12, the steam introduction part 121 is connected to the high-temperature reheat steam pipe F40, and the steam discharge parts 122a and 122b are connected to the crossover pipes F12a and F12b.

  When normal operation is performed in the steam turbine 10, the steam discharged from the high pressure turbine 11 flows through the high-temperature reheat steam pipe F <b> 40 through the reheat steam combination valve 40 in the intermediate pressure turbine 12. It flows into the introduction part 121. The steam discharged from the high-pressure turbine 11 is heated again by a reheater (not shown) of a boiler (not shown) and then flows into the intermediate-pressure turbine 12 as a working medium. The steam is discharged from the steam discharge portions 122a and 122b to the crossover pipes F12a, F12b, and F12c after performing work in the intermediate pressure turbine 12.

  As can be seen from FIG. 1, the intermediate pressure turbine 12 is a double-flow exhaust type, and in the direction along the rotation axis of the turbine rotor (not shown), from the steam introducing portion 121 provided in the central portion, to one end side. The steam flows toward the steam discharge part 122a provided and the steam discharge part 122b provided on the other end side, and is exhausted.

  Although not shown, the intermediate pressure turbine 12 is a multistage axial turbine similar to the high pressure turbine 11, and has a plurality of turbine stages (not shown) in the turbine casing (not shown). Are lined up along the axis of rotation.

  The turbine casing of the intermediate pressure turbine 12 has, for example, a double structure like the high pressure turbine 11 and has an inner casing (not shown) and an outer casing (not shown). The inner casing accommodates the turbine rotor inside. The inner casing includes an upper half (not shown) of the inner casing and a lower half (not shown) of the inner casing, and is configured by combining both. The outer casing accommodates the inner casing inside. The outer casing includes an upper half (not shown) of the outer casing and a lower half (not shown) of the outer casing, and is configured by combining the two.

  In the intermediate pressure turbine 12, the steam introduction part 121 is an opening that penetrates the lower half part of the inner casing and the lower half part of the outer casing, and is a flow path that introduces steam into the inner casing. The steam discharge portions 122a and 122b are openings that penetrate between the inside and the outside of the upper half of the outer casing, and are passages that discharge the steam that has flowed out 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 123a, 123b, 124a, and 124b in addition to the above. The plurality of through holes 123a, 123b, 124a, 124b are formed so as to penetrate the lower half of the outer casing. Here, the plurality of through holes 123a, 123b, 124a, and 124b are arranged so as to be spaced apart in the direction along the rotation axis of the turbine rotor. That is, a plurality of through holes 123a and 124a are arranged from the central portion toward one end side, and a plurality of through holes 123b and 124b are arranged from the central portion toward the other end side.

  Although details will be described later, when the turning operation is performed in the steam turbine system 1, in the present embodiment, the intermediate pressure turbine 12 is cooled by being supplied with cooling air from the turbine cooling device 50, similarly to the high pressure turbine 11. The Here, the cooling air flows into the inner casing through the steam introduction part 121. The inflowing cooling air flows through the inside of the inner casing, and is then discharged to the outside from the steam discharge portions 122a and 122b.

  At the same time, in the present embodiment, the cooling air supplied from the turbine cooling device 50 flows into the space between the inner casing and the outer casing through the plurality of through holes 123a, 123b, 124a, 124b. Then, after the cooling air flows through the space between the inner casing and the outer casing, the cooling air is discharged to the outside from the steam discharge portions 122a and 122b.

  In addition to the above, the intermediate-pressure turbine 12 is provided with an elongation difference measuring unit (not shown) that measures an elongation difference between the turbine rotor and the turbine casing, as in the case of the high-pressure turbine 11. Further, the intermediate pressure turbine 12 is a temperature difference measuring unit (not shown) that measures the temperature difference between the inside of the steam chamber located at the inlet of the steam passage through which steam flows inside the turbine casing and the outside of the steam chamber. Is installed. The result of the difference in elongation between the turbine rotor 300 and the turbine casing 110 and the result of the temperature difference between the inside and the outside of the steam chamber measured in the temperature difference measuring unit measured in the elongation difference measuring unit are measured data D10. Is output to the turbine cooling device 50.

[A-1-3] First low-pressure turbine 13 and second low-pressure turbine 14
Among the steam turbines 10, the first low-pressure turbine 13 includes a steam introduction part 131 and steam discharge parts 132 a and 132 b as shown in FIG. 1. In the first low-pressure turbine 13, the steam introduction part 131 is connected to the crossover pipe F12c, and the steam discharge parts 132a and 132b are connected to the piping parts F13a and F13b.

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

  When normal operation is performed in the steam turbine 10, the steam discharged from the intermediate pressure turbine 12 flows through the crossover pipes F12a, F12b, and F12c in the first low pressure turbine 13 and the second low pressure turbine 14. Then, it flows into the steam inlets 131 and 141 as a working medium. Here, in the crossover pipes F12a, F12b, and F12c, the steam discharged from the intermediate pressure turbine 12 joins at the joining point J12a, then branches at the branching point J12b, and the steam introducing portion of the first low-pressure turbine 13 131 and the steam introduction part 141 of the second low-pressure turbine 14 respectively. The steam is discharged from the steam discharge portions 132a, 132b, 142a, 142b after performing work in the first low-pressure turbine 13 and the second low-pressure turbine 14. The steam discharged from each of the first low-pressure turbine 13 and the second low-pressure turbine 14 flows into the condenser 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 double-flow exhaust type, similar to the intermediate-pressure turbine 12, along the rotation axis of the turbine rotor (not shown). In the direction, steam flows from the steam inlets 131 and 141 provided in the central portion toward the steam outlets 132a and 142a provided on one end side and the steam outlets 132b and 142b provided on the other end side. It flows and is exhausted.

  Although not shown, each of the first low-pressure turbine 13 and the second low-pressure turbine 14 is a multistage axial flow turbine, like the high-pressure turbine 11 and the intermediate-pressure turbine 12, and includes a turbine casing. Inside the (not shown), a plurality of turbine stages (not shown) are arranged along the rotation axis.

  Although details will be described later, when the turning operation is performed in the steam turbine system 1, 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 intermediate-pressure turbine 12. Then, cooling air is supplied from the turbine cooling device 50 to be cooled. Here, the cooling air flows into the turbine casing through the steam introduction portions 131 and 141. The inflowing cooling air flows through the inside of the turbine casing and is then discharged to the outside from the steam discharge portions 132a, 132b, 142a, 142b.

[A-2] Turbine cooling device 50
In the steam turbine system 1, the turbine cooling device 50 includes a cooling air supply unit 51 and a control unit 52 as shown in FIG. 1, and is configured to cool the steam turbine 10.

[A-2-1] Cooling air supply unit 51
Of the turbine cooling device 50, the cooling air supply unit 51 includes a blower 511 and a cooling air piping system 512. The cooling air supply unit 51 supplies the cooling air blown by the blower unit 511 to the inside of the turbine casing of the steam turbine 10 via the cooling air piping system 512 in the turning operation performed after stopping the normal operation of the steam turbine. By doing so, 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 inner casing 201 of the high-pressure turbine 11 and also supplies cooling air to the space between the inner casing 201 and the outer casing 202.

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

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

[A-2-1-1] Blower 511
Of the cooling air supply unit 51, the blower 511 includes, for example, a blower (not shown).

  In the air blower 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, and F14b, and a plurality of manual valves V51, V511 to V514, V521. V525, V13a, V13b, V14a, V14b and a plurality of automatic valves M51, M511, M521-M523 are included.

  In the cooling air piping system 512, each of the plurality of piping parts F51, F511 to F514, F521 to F525, F13a, F13b, F14a, and F14b is a flow path through which the cooling air blown by the blowing part 511 flows. It is comprised using.

  One end of the piping part F51 (first piping part) is connected to the air blowing part 511, and the other end is connected to the connection point J30a of the main steam pipe F30a. The pipe part F51 is provided with a plurality of connection points J51a to J51d sequentially from one end to the other end. In the piping part F51, an automatic valve M51 and a manual valve V51 are sequentially installed from one end to the other end between the other end and the connection point J51d provided on the other end side.

  One end of the piping part F511 (second piping part) is connected to a connection point J51d provided on the most other end side in the piping part F51 (first piping part). And the other end of the piping part F511 is connected to the through hole 113a of the high-pressure turbine 11. The pipe portion F511 is provided with a connection point J511 between one end and the other end. In the piping part F511, the automatic valve M511 is installed between one end and the connection point J511. Moreover, in the piping part F511, the manual valve V511 is installed between the other end and the connection point J511.

  One end of the pipe part F512 (third pipe part) is connected to a connection point J511 of the pipe part F511 (second pipe part). The other end of the pipe part F512 is connected to the through hole 113b of the high-pressure turbine 11. In the piping part F512, the manual valve V512 is installed between one end and the other end.

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

  One end of the pipe part F514 (fifth pipe part) is connected to a connection point J513 of the pipe part F513 (fourth pipe part). And the other end of the piping part F514 is open to the outside. The pipe portion F514 is provided with a plurality of connection points J514a to J514d sequentially from one end to the other end. In the piping part F514, the manual valve V514 is installed between one end and the connection point J514a provided on the most end side.

  One end of the piping part F521 (sixth piping part) is connected to a connection point J51c provided second from the other end side in the piping part F51 (first piping part). And the other end of the piping part F521 is connected to the connection point J40 of the high-temperature reheat steam pipe F40. In the piping part F51, between one end and the other end, an automatic valve M521 and a manual valve V521 are sequentially installed from one end to the other end.

  One end of the piping part F522 (seventh piping part) is connected to a connection point J51b provided third from the other end side in the piping part F51 (first piping part). The other end of the piping part F522 is connected to the through hole 124a of the intermediate pressure turbine 12. The pipe part F522 is provided with a connection point J522 between one end and the other end. In the piping part F522, an automatic valve M522 is installed between one end and the connection point J522. Moreover, in the piping part F522, the manual valve V522 is installed between the other end and the connection point J522.

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

  One end of the pipe part F524 (the ninth pipe part) is connected to a connection point J522 of the pipe part F522 (the seventh pipe part). The other end of the piping part F524 is connected to the through hole 124b of the intermediate pressure turbine 12. The piping part F524 is provided with a manual valve V524 between one end and the other end.

  One end of the pipe part F525 (tenth pipe part) is connected to a connection point J523 of the pipe part F523 (eighth pipe part). The other end of the piping part F525 is connected to the through hole 123b of the intermediate pressure turbine 12. The piping part F525 is provided with a manual valve V525 between one end and the other end.

  One end of the pipe part F13a (the eleventh pipe part) is connected to the steam discharge part 132a of the first low-pressure turbine 13. And piping part F13a has the other end connected to connecting point J514a provided on the most end side in piping part F514 (fifth piping part). The piping part F13a is provided with a manual valve V13a between one end and the other end.

  One end of the pipe part F13b (the twelfth pipe part) is connected to the steam discharge part 132b of the first low-pressure turbine 13. And piping part F13b has the other end connected to connecting point J514b provided second from one end side in piping part F514 (fifth piping part). The piping part F13b is provided with a manual valve V13b between one end and the other end.

  One end of the piping part F <b> 14 a (13th piping part) is connected to the steam discharge part 142 a of the second low-pressure turbine 14. And piping part F14a has the other end connected to connecting point J514c provided third from one end side in piping part F514 (fifth piping part). The piping part F14a is provided with a manual valve V14a between one end and the other end.

  One end of the pipe part F <b> 14 b (14th pipe part) is connected to the steam discharge part 142 b of the second low-pressure turbine 14. And the other end of the pipe part F14b is connected to the connection point J514d provided on the other end side in the pipe part F514 (fifth pipe part). The piping part F14b is provided with a manual valve V14b between one end and the other end.

  Although details will be described later, in the cooling air piping system 512, the piping part F <b> 51 (first cooling air supply part) supplies cooling air to the inside of the inner casing 201 in the turbine casing 110 of the high-pressure turbine 11. Used. The piping parts F511 and F512 (second cooling air supply part) are used when cooling air is supplied to the space between the inner casing 201 and the outer casing 202 in the turbine casing 110 of the high-pressure turbine 11.

  In the cooling air piping system 512, the piping part F 521 (first cooling air supply part) is used when supplying cooling air to the inside of the inner casing of the turbine casing of the intermediate pressure turbine 12. The piping parts F522 to F525 (second cooling air supply part) are used when cooling air is supplied to the space between the inner casing and the outer casing among the turbine casings of the intermediate pressure turbine 12.

  Although not shown, in the cooling air piping system 512, each of the automatic valves M51, M511, M521 to M523 receives the control signal CTL52 output from the control unit 52, and according to the control signal CTL52 The opening degree of the valve is automatically adjusted. For example, each of the automatic valves M51, M511, M521 to M523 includes an actuator, and the actuator varies the distance between the valve body and the valve seat in accordance with the control signal CTL52.

[A-2-1] Control unit 52
In the turbine cooling device 50, the control unit 52 is configured to control the operation of the cooling air supply unit 51 in the turning operation performed after stopping the normal operation of the steam turbine. The control unit 52 includes an arithmetic unit (not shown) and a memory device (not shown), and the arithmetic unit performs arithmetic 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 operation | movement of each part.

  Specifically, the control unit 52 controls the operation of the air blowing unit 511 by outputting a control signal CTL 52 to the air blowing unit 511. Further, the control unit 52 controls the operations of the automatic valves M51, M511, M521 to M523 by outputting a control signal CTL52 to the automatic valves M51, M511, M521 to M523 of the cooling air piping system 512.

  As described above, the control unit 52 receives the result of the differential expansion and the result of the temperature difference from the steam turbine 10 as the actual measurement data D10. And the control part 52 outputs the control signal CTL52 using the input actual measurement data D10.

[B] Operation Hereinafter, an operation when the turbine cooling device 50 forcibly cools the steam turbine 10 in the 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, the turbine cooling device 50 receives a command for performing the forced cooling operation, and outputs the control signal CTL 52 to the cooling air supply unit 51. Then, based on the control signal CTL 52, the cooling air supply unit 51 supplies the cooling air to the inside of the turbine casing of the steam turbine 10.

  In the cooling air supply unit 51, the cooling air blown by the blowing unit 511 is supplied to the inside of the turbine casing of the steam turbine 10 via the cooling air piping system 512. In the cooling air piping system 512, the plurality of manual valves V51, V511 to V512, V514, V521 to V525, V13a, V13b, V14a, and V14b are all opened, and the plurality of automatic valves M51, M511, M521 The valve opening of M523 is adjusted based on the control signal CTL52, and the cooling air flows through the plurality of pipe portions F51, F511 to F514, F521 to F525, F13a, F13b, F14a, and F14b. Of the above, in the piping parts F13a, F13b, F14a, and F14b, a part of the cooling air that has passed through the first low-pressure turbine 13 or the second low-pressure turbine 14 flows. The remaining air flows through the first low-pressure turbine 13 or the second low-pressure turbine 14 and then flows into the condenser 60 and is discharged to the outside through the vacuum break valve V60.

  FIG. 4 is a flowchart showing an outline of an 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] First step (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 the present embodiment, the predetermined flow rate is a flow rate obtained by performing numerical calculation in advance so that each part of the steam turbine 10 is in an optimal state. Specifically, the predetermined flow rate is the difference in elongation between the turbine rotor (such as reference numeral 300 in FIG. 2) and the turbine casing (such as reference numeral 110 in FIG. 2) and the turbine of the steam turbine 10. Numerical values so that the temperature difference between the inside of the steam chamber located at the inlet of the steam flow path through which steam flows inside the casing (such as reference numeral 110 in FIG. 2) and the outside of the steam chamber is within a set range at a predetermined time. The flow rate obtained by calculation.

  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 the cooling air to the steam turbine 10 at a predetermined flow rate for a predetermined time (see FIG. 1). 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 cooling each part of the steam turbine 10 with a predetermined flow rate. Distribute and supply air.

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

  In this case, in the cooling air supply unit 51, the cooling air blown by the blower unit 511 flows through the main steam pipes F30a and F30b, and then flows through the pipe portion F51 of the cooling air piping system 512. It flows into the steam inlets 111a and 111b. The cooling air flows into the steam inlets 111a and 111b at a predetermined flow rate by the automatic valve M51 (see FIG. 1). The cooling air that has flowed into the steam introducing portions 111a and 111b flows through the inside of the inner casing 201 in the turbine casing 110 and then is discharged from the steam discharging portion 112 to the outside (see FIG. 2). That is, a predetermined flow rate of cooling air is supplied to a steam flow path through which steam flows as a working medium in the turbine casing 110 of the high-pressure turbine 11.

  At the same time, the cooling air blown by the blower 511 flows through the plurality of pipes F51, F511, and F512 of the cooling air pipe system 512, and then passes through the through holes 113a and 113b formed in the high-pressure turbine 11. 11 flows into the interior. The cooling air flows into the high-pressure turbine 11 through the through holes 113a and 113b at a predetermined flow rate by the automatic valve M511 (see FIG. 1). The through holes 113a and 113b of the high-pressure turbine 11 are provided with a first tubular body 250a and a second tubular body 250b, and the cooling air is a cooling air discharge port formed in the first tubular body 250a. It flows into the space between the inner casing 201 and the outer casing 202 through H250a and the cooling air discharge port H250b formed in the second tubular body 250b (see FIG. 2). Then, the cooling air flows through the space between the inner casing 201 and the outer casing 202, and then is discharged from the steam discharge unit 112 to the outside. That is, cooling air having a predetermined flow rate is supplied to a space located outside the steam flow path in the turbine casing 110 that constitutes the high-pressure turbine 11.

  The cooling air discharged from the steam discharge unit 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 discharged to the outside, and the other part flows to the pipe part F513 at the connection point J11. The cooling air flowing through the pipe part F513 flows to the pipe part F514 at the connection point J513. The cooling air flowing through the piping part F514 is released to the outside.

  In addition to the above, in this embodiment, the turbine cooling device 50 supplies cooling air with 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, in the cooling air supply unit 51, the cooling air blown by the blowing unit 511 flows through the plurality of piping parts F51 and F521 of the cooling air piping system 512, and then passes through the high-temperature reheat steam pipe F40. It flows into the steam introduction part 121 of the intermediate pressure turbine 12. The cooling air flows into the steam introduction part 121 at a predetermined flow rate by the automatic valve M521 (see FIG. 1). The cooling air that has flowed into the steam introduction part 121 is not shown, but after flowing through the inside of the inner casing of the turbine casing, the cooling air is discharged to the outside from the steam discharge parts 122a and 122b (see FIG. 1). ). That is, cooling air having a predetermined flow rate is supplied to a steam flow path through which steam as a working medium flows in the turbine casing of the intermediate pressure turbine 12.

  At the same time, the cooling air blown by the blowing section 511 flows through the plurality of piping sections F51, F522 to F525 of the cooling air piping system 512, and then the through holes 123a, 124a, 123b, 124b formed in the intermediate pressure turbine 12. Through the intermediate pressure turbine 12. The cooling air flows into the intermediate pressure turbine 12 through the through holes 123a, 124a, 123b, and 124b at a predetermined flow rate by the automatic valves M522 and M523 (see FIG. 1). Although not shown, the cooling air flowing into the through holes 123a, 124a, 123b, and 124b flows into the space between the inner casing and the outer casing that constitute the turbine casing (see FIG. 2). Then, after the cooling air flows through the space between the inner casing and the outer casing, the cooling air is discharged to the outside from the steam discharge portions 122a and 122b. That is, cooling air having a predetermined flow rate is supplied to a space located outside the steam flow path in the turbine casing constituting the intermediate pressure turbine 12.

  Cooling air discharged from the steam discharge portions 122a and 122b of the intermediate pressure turbine 12 flows through the crossover tubes F12a, F12b, and F12c. The cooling air flowing through the crossover tubes F12a, F12b, F12c flows into the first low-pressure turbine 13 and the second low-pressure turbine 14, respectively. Then, the cooling air flows through the first low-pressure turbine 13 and the second low-pressure turbine 14, and then the steam discharge portions 132 a and 132 b of the first low-pressure turbine 13 and the steam of the second low-pressure turbine 14. It is discharged from the discharge portions 142a and 142b.

  A part of the cooling air discharged from the steam discharge portions 132a and 132b of the first low-pressure turbine 13 flows through the piping portions F13a and F13b and then flows into the piping portion F514 at the connection points J514a and J514b. Similarly, some of the cooling air discharged from the steam discharge portions 142a and 142b of the second low-pressure turbine 14 flows through the piping portions F14a and F14b and then flows into the piping portion F514 at the connection points J514c and J514d. And the cooling air which flows through the piping part F514 is discharge | released outside.

[B-2] Second step (ST2)
Next, as shown in FIG. 4, the flow rate of the cooling air is adjusted according to the actual measurement data (ST2).

  Here, in the steam turbine 10, based on the result of measuring the difference in elongation between the turbine rotor (such as reference numeral 300 in FIG. 2) and the turbine casing (such as reference numeral 110 in FIG. 2), the control section 52 performs the cooling air supply section. The operation of 51 is controlled. At the same time, the result of measuring the temperature difference between the inside of the steam chamber located at the inlet of the steam flow path through which steam flows inside the turbine casing (such as reference numeral 110 in FIG. 2) of the steam turbine 10 and the outside of the steam chamber. Based on the above, 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 look-up table that associates the above-described difference in elongation and temperature and the flow rate.

  Specifically, when the turbine rotor 300 of the high-pressure turbine 11 is longer than the set range based on the measurement result of the difference in elongation, the automatic valve M511 is controlled so that the flow rate of the cooling air flowing through the pipe portion F511 decreases. Adjust the opening. That is, the flow rate of the cooling air is adjusted so that the temperature of the turbine casing 110 becomes lower than the temperature of the turbine rotor 300 and the temperature of both approaches.

  When the turbine rotor 300 of the high-pressure turbine 11 is shorter than the set range according to the result of the difference in elongation, the opening degree of the automatic valve M51 is adjusted so that the flow rate of the cooling air flowing through the pipe portion F51 is reduced. That is, the flow rate of the cooling air is adjusted so that the temperature of the turbine rotor 300 becomes lower than the temperature of the turbine casing 110 and the temperature of both approaches.

  Furthermore, the opening degree of the automatic valve M51 is adjusted so that the flow rate of the cooling air flowing through the piping part F51 is reduced when the temperature of the inner peripheral surface is lower than the temperature of the outer peripheral surface, as a result of the temperature difference. To do. That is, the flow rate of the cooling air is adjusted so that the temperature of the turbine rotor 300 becomes lower than the temperature of the turbine casing 110 and the temperature of both approaches.

  Also in the case of the intermediate pressure turbine 12, the flow rate of the cooling air is adjusted in the same manner as in 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. In the first step (ST1), the control unit 52 controls the operation of the cooling air supply unit 51 so that the cooling air supply unit 51 supplies the cooling air at a predetermined flow rate. For this reason, in this embodiment, in the first step (ST1), each part of the steam turbine 10 is cooled so as to approach an optimum state.

  Thereafter, in the present embodiment, in the second step (ST2), the control unit 52 measures an elongation difference between the turbine rotor (reference numeral 300 in FIG. 2) and the turbine casing (reference numeral 110 in FIG. 2). Based on the result and the result of measuring the temperature difference between the inner peripheral surface of the steam chamber located at the inlet of the steam flow path through which steam flows in the turbine casing (such as reference numeral 110 in FIG. 2) and the outer peripheral surface of the steam chamber. The operation of the cooling air supply unit 51 is controlled. For this reason, in the present embodiment, in the first step, when the difference in elongation and the temperature difference are not within a predetermined range, in the second step, the difference in elongation and the temperature described above. The difference can be in a predetermined range.

  Therefore, in the present embodiment, the steam turbine 10 can be cooled in a short time, and the above-described difference in elongation and the above-described temperature difference can be in a predetermined range. An alarm is generated when the above-described difference in elongation or the above-described temperature difference is outside a predetermined range, but in this embodiment, the generation of the alarm can be prevented.

  Further, the turbine cooling device 50 of the present embodiment is configured such that cooling air flows along the rotation axis AX of the turbine rotor 300 in the space between the inner casing 201 and the outer casing 202. Specifically, as described above, the first tubular body 250a and the second tubular body 250b extending along the radial direction of the turbine rotor 300 are provided. The first tubular body 250a and the second tubular body 250b include cooling air discharge ports H250a and H250b penetrating along the rotation axis AX of the turbine rotor 300, and the cooling air is supplied to the cooling air discharge port H250a. , H250b flows into the space between the inner casing 201 and the outer casing 202 (see FIG. 2). For this reason, since this embodiment can relieve the temperature difference between the inside and the outside of the inner casing 201, the problem of the thermal stress of the inner casing 201 can be solved and the steam turbine 10 can be efficiently cooled. Can be done.

  In addition, in this embodiment, the 1st tubular body 250a is a balance plug attachment pipe to which a balance plug (illustration omitted) is attached, for example. The second tubular body 250b is, for example, a thermocouple protection cylinder that houses a thermocouple (not shown) therein. 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. For this reason, in this embodiment, supply of cooling air is realizable by easy process.

[D] Modified Example In the above embodiment, in the second step (ST2), the result of measuring the difference in elongation between the turbine rotor (reference numeral 300 in FIG. 2) and the turbine casing (reference numeral 110 in FIG. 2). And the result of measuring the temperature difference between the inner peripheral surface of the steam chamber located at the inlet of the steam flow path through which steam flows in the turbine casing (reference numeral 110 in FIG. 2, etc.) and the outer peripheral surface of the steam chamber. The case where the operation of the cooling air supply unit 51 is controlled has been described, but the present invention is not limited to this. The operation of the cooling air supply unit 51 may be controlled according to at least one of the difference in elongation and the difference in temperature.

  In the high pressure turbine 11 of the above embodiment, the cooling air that flows through the space between the inner casing 201 and the outer casing 202 does not merge with the cooling air that flows inside the inner casing 201, and is exhausted from the high pressure turbine 11. However, the present invention is not limited to this. The high pressure turbine 11 is configured such that the cooling air that flows through the space between the inner casing 201 and the outer casing 202 joins the cooling air that flows through the inner casing 201 and then is exhausted from the high pressure turbine 11. Also good.

  In the above embodiment, cooling is performed based on the temperature difference between the inner peripheral surface of the steam chamber located at the inlet of the steam flow path in which the turbine stage is disposed inside the turbine casing 110 and the outer main surface of the steam chamber. Although the case where operation | movement of the air supply part 51 was controlled was demonstrated, it is not restricted to this. The operation of the cooling air supply unit 51 may be controlled based on the temperature difference between the upper half casing and the lower half casing.

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

Second Embodiment
[A] Configuration FIG. 5 is a diagram schematically illustrating a steam turbine system 1 according to the second embodiment. In FIG. 5, the flow path of the cooling air supplied as a cooling medium to the steam turbine 10 is indicated by solid arrows as in FIG.

  As shown in FIG. 5, in the cooling air supply part 51 of this embodiment, the cooling air piping system 512 differs from the case of 1st Embodiment (refer FIG. 1), and some manual valves V51, V511, V512. V521, V522, V523, V524, and V525 are not installed. And the number of the automatic valves M51, M511, M512, M521 to M525 is larger than in the case of the first embodiment (see FIG. 1). This embodiment is the same as the case of the first embodiment except for the above points and related points. For this reason, in the present embodiment, the description overlapping with the case of the above embodiment is omitted as appropriate.

  In the present embodiment, the automatic valves M51, M511, M512, M521 to M525 are connected to the pipe portions F51, F511, F512, F521 to F525 connected to the plurality of supply ports to which the cooling air is supplied in the steam turbine 10, respectively. Is installed.

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

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

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

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

  The automatic valve M522 is installed between the other end (the through-hole 124a side of the intermediate pressure turbine 12) and the connection point J522 in the pipe part F522 (seventh pipe part).

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

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

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

[B] Operation In this embodiment, when performing the forced cooling operation for forcibly cooling the steam turbine 10, first, in the first step (ST1), as in the case of the first embodiment (see FIG. 4), Cooling air is supplied at a predetermined flow rate. Next, in the second step (ST2), the flow rate of the cooling air is adjusted according to the actually 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 due to the above-described difference in elongation, the cooling air flowing through the pipe portion F511 is the same as in the first embodiment. The opening degree of the automatic valves M511 and M512 is adjusted so that the flow rate of

  On the other hand, when the turbine rotor 300 of the high-pressure turbine 11 is shorter than the set range due to the difference in elongation described above, the automatic valve M51 is opened so that the flow rate of the cooling air flowing through the pipe portion F51 decreases. Adjust the degree.

  Furthermore, the opening degree of the automatic valve M51 is adjusted so that the flow rate of the cooling air flowing through the piping part F51 is reduced when the temperature of the inner peripheral surface is lower than the temperature of the outer peripheral surface, as a result of the temperature difference described above. To do.

  Also in the case of the intermediate pressure turbine 12, the flow rate of the cooling air is adjusted in the same manner as in the case of the high pressure turbine 11.

[C] Summary (action, effect, etc.)
In this embodiment, unlike the case of the first embodiment, some manual valves V51, V511, V512, V521, V522, V523, V524, and V525 (see FIG. 1) were not installed and not installed. Automatic valves M51, M511, M512, M521, M522, M523, M524, and M525 are provided so as to function as manual valves. For this reason, simplification of the apparatus can be easily realized.

  In the present embodiment, as described above, the automatic valves M51, M511 are connected to the pipe portions F51, F511, F512, F521 to F525 connected to the plurality of supply ports to which the cooling air is supplied in the steam turbine 10, respectively. M512, M521 to M525 are installed. For this reason, in this embodiment, cooling can be performed more efficiently.

<Third Embodiment>
[A] Configuration FIG. 6 is a diagram schematically illustrating a steam turbine system 1 according to the third embodiment. In FIG. 6, similarly to FIG. 1, the flow path of the cooling air supplied as a cooling medium to the steam turbine 10 is indicated by solid arrows.

  FIG. 7 is a cross-sectional view showing the high-pressure turbine 11 in the steam turbine system 1 according to the third embodiment. In FIG. 7, as in FIG. 2, a vertical plane (xz plane) defined by a direction (x direction) along the rotation axis AX in the horizontal direction (x direction, y direction) and a vertical direction (z direction). ) Is shown.

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

  In the present embodiment, the cooling air discharge pipe 600 is installed inside the turbine casing 110 in the high-pressure turbine 11 as shown in FIG.

  FIG. 8 is a diagram showing the cooling air discharge pipe 600 and the first tubular body 250a in the steam turbine system 1 according to the first embodiment. FIG. 8 shows a state when the direction (x direction) along the rotation axis AX is taken as a line of sight, as in FIG.

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

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

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

[B] Summary (action, effect, etc.)
As described above, the cooling air discharge pipe 600 is installed in the present embodiment. The cooling air discharge pipe 600 is formed such that a plurality of cooling air discharge ports H600 are arranged at equal intervals around the outer peripheral surface of the inner casing 201. For this reason, in this embodiment, cooling air can be uniformly supplied to the space between the inner casing 201 and the outer casing 202.

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

  In particular, the present embodiment is suitable when the high-pressure turbine 11 cannot provide the through hole 113b and it is difficult to install the second tubular body 250b.

<Others>
Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 ... Steam turbine system, 10 ... Steam turbine, 11 ... High pressure turbine, 12 ... Medium pressure turbine, 13 ... 1st low pressure turbine, 14 ... 2nd low pressure turbine, 20 ... Main steam stop valve, 30 ... Steam control valve, 40 ... reheat steam combination valve, 50 ... turbine cooling device, 51 ... cooling air supply unit, 52 ... control unit, 110 ... turbine casing, 201 ... inner casing, 202 ... outer casing, 211 ... upper half of inner casing, 212 ... Inner casing lower half, 221 ... outer casing upper half, 222 ... outer casing lower half, 250a ... first tubular body, 250b ... second tubular body, 300 ... turbine rotor, 500a, 500b ... sleeve, 511 ... Blower part, 512 ... Cooling air piping system, 600 ... Cooling air discharge pipe

Claims (6)

A turbine cooling device for cooling a steam turbine that houses a turbine rotor inside a turbine casing,
A cooling air supply unit for supplying cooling air into the turbine casing;
A control unit for controlling the operation of the cooling air supply unit during the turning operation,
The control unit controls an operation of the cooling air supply unit so that the cooling air supply unit supplies the cooling air at a predetermined flow rate, and then determines an elongation difference between the turbine rotor and the turbine casing. The cooling is based on at least one of the measurement result and the result of measuring the temperature difference between the inner peripheral surface of the steam chamber located at the inlet of the steam flow path through which steam flows in the turbine casing and the outer peripheral surface of the steam chamber. Controlling the operation of the air supply unit,
Turbine cooling device. The turbine casing is
An inner casing that houses the turbine rotor;
An outer casing for accommodating the inner casing therein,
The cooling air supply unit
A first cooling air supply unit for supplying the cooling air into the inner casing;
A second cooling air supply unit that supplies the cooling air to a space between the inner casing and the outer casing;
The control unit is configured to control the first cooling air supply unit and the second cooling air supply unit so that the first cooling air supply unit and the second cooling air supply unit supply the cooling air at a predetermined flow rate. After controlling the operation, the operation of the first cooling air supply unit and the second cooling air supply unit is controlled based on at least one of the result of measuring the elongation difference and the result of measuring the temperature difference.
The turbine cooling device according to claim 1. In the space between the inner casing and the outer casing, the cooling air supplied by the second cooling air supply unit is configured to flow along the rotation axis of the turbine rotor.
The turbine cooling device according to claim 2. A tubular body extending along the radial direction of the turbine rotor,
The tubular body includes a cooling air discharge port penetrating along the rotation axis of the turbine rotor, and the cooling air supplied by the second cooling air supply unit is connected to the inner casing from the cooling air discharge port. Flowing into the space between the outer casing,
The turbine cooling device according to claim 3. The tubular body is
A first tubular body;
A 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 claim 4. A cooling air discharge pipe installed so as to surround the outer peripheral surface of the inner casing,
The cooling air discharge pipe has a plurality of cooling air discharge ports from which the cooling air is discharged, and the plurality of cooling air discharge ports are arranged at equal intervals around the outer peripheral surface of the inner casing, The cooling air supplied by the second cooling air supply unit flows from each of the plurality of cooling air discharge ports to a space between the inner casing and the outer casing;
The turbine cooling device according to claim 3.

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