JP2010285924A - Steam turbine and stationary part sealing structure thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve efficiency by inhibiting steam leak of a seal part between stationary parts partitioning spaces in which pressures are different in a steam turbine. <P>SOLUTION: This steam turbine includes a first and a second stationary member 101, 102 which are not mutually fixed and which form a first, a second and a third space 13, 14, 15 in which pressure are different, a first seal part 21 partitioning the first and the second space 13, 14, and a second seal part 22 partitioning the second and the third space. The first seal part 21 is composed to be sealed by pressing the first and the second stationary member 101, 102 against each other by force pressing the same against each other by pressure difference in the first and the second space 13, 14. A seal member 30 is disposed in a gap where the first and the second stationary member 101, 102 are adjacent to each other in the second seal part 22. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a steam turbine and a stationary part seal structure thereof.

  In recent years, in order to improve the operational economy of power plants and improve power generation efficiency, it has become an important issue to improve turbine performance.

  The loss inside the turbine is mainly an essential loss such as a blade profile loss, a secondary loss, or an exhaust loss at the final stage, but a steam leakage is a more easily understood loss. If the amount of steam leakage is large, the amount of steam working is reduced accordingly, so the loss naturally increases. A number of seal structures have been developed to reduce this amount of steam leakage, but these are mainly related to steam leakage that occurs between the rotating part and the stationary part, such as blades, rotors and nozzles, and rotors and grounds. is there. Actually, the largest steam leakage loss is between the blade / rotor and the nozzle, so it is natural to put effort into the seal structure of this part. There are some places where loss due to steam leakage is seen. In particular, steam leakage loss occurs in a double casing structure (see Patent Document 1) having two or more boundaries that separate spaces having different pressures and temperatures by combining stationary parts such as a turbine casing, a turbine nozzle, and a ground casing. It is noticeable.

  The steam conditions inside the turbine depend on the plant, but may be 25 MPa or more and 600 ° C. or more due to recent high performance. The outside of the turbine is at atmospheric pressure. In a double-chamber structure steam turbine, between the inside and outside of the turbine, a high-temperature, high-pressure steam is prevented from flowing out, and a stationary part that is doubled is installed to ease the pressure / temperature difference. Yes. In order to separate at least three spaces having different pressures and temperatures by the stationary portion, there are at least two boundaries. At one boundary, a structure that seals the stationary parts by surface contact with each other due to a pressure difference (hereinafter referred to as a “steam joint” seal structure) is adopted. On the other hand, since it is necessary to escape thermal expansion at other boundaries, the stationary portions cannot be brought into surface contact with each other, and therefore, a seal structure is adopted in which the clearance of the fitting portion is made as small as possible.

Japanese Patent Laid-Open No. 2001-2221012

  In the seal structure between the stationary parts of the steam turbine as described above, the seal by the steam joint can surely eliminate the leakage amount, but the seal not by the steam joint is completely reduced although the clearance is small. The amount of leakage cannot be reduced to zero. The loss due to this leakage has been found to be a level that cannot be ignored in recent analyses, and if there are many such points, the loss will be excessive.

  The present invention has been made in order to solve the above-described problems of the background art, and in a steam turbine, the steam leakage of a seal portion between stationary portions that partition spaces having different pressures is suppressed, thereby improving the efficiency of the steam turbine. It aims to plan.

  In order to achieve the above object, a steam turbine according to the present invention includes first, second, and third spaces having different pressures, and a first seal portion that partitions between the first and second spaces. A steam turbine having first and second stationary members that are not fixed to each other, forming a second seal portion that partitions between the second and third spaces. The portion is configured such that the first and second stationary members are pressed against each other due to a difference in pressure in the first and second spaces and sealed, and the second seal portion includes The seal member is disposed in a gap where the one stationary member and the second stationary member are close to each other.

  Further, the steam turbine stationary part seal structure according to the present invention includes first, second and third spaces having different pressures, a first seal part which partitions between the first and second spaces, A stationary part sealing structure for a steam turbine having first and second stationary members that are not fixed to each other, and that forms a second seal part that partitions between the second and third spaces, The first seal portion is configured such that the first and second stationary members are pressed against each other due to a difference in pressure in the first and second spaces, and the second seal portion includes A sealing member is disposed in a gap where the first stationary member and the second stationary member are close to each other.

  According to the present invention, in the steam turbine, steam leakage of the seal portion between the stationary portions that partition the spaces having different pressures is suppressed, and the efficiency of the steam turbine can be improved.

It is a fragmentary longitudinal cross-sectional view which shows the principal part of 1st Embodiment of the steam turbine which concerns on this invention, Comprising: The fragmentary longitudinal cross-sectional view which expands and shows the I section of FIG. The fragmentary longitudinal cross-section which shows the principal part of 1st Embodiment of the steam turbine which concerns on this invention. FIG. 3 is a partial vertical cross-sectional view showing a main part of the first embodiment of the steam turbine according to the present invention, and is an enlarged partial vertical cross-sectional view showing a part III in FIG. 1. It is a fragmentary longitudinal cross-sectional view which shows the principal part of 1st Embodiment of the steam turbine which concerns on this invention, Comprising: The fragmentary longitudinal cross-sectional view which expands and shows the IV section of FIG. FIG. 3 is a partial longitudinal sectional view showing a main part of the first embodiment of the steam turbine according to the present invention, and is an enlarged partial longitudinal sectional view showing a V part in FIG. 2. It is a partial longitudinal cross-sectional view which shows the principal part of 2nd Embodiment of the steam turbine which concerns on this invention, Comprising: The partial longitudinal cross-sectional view corresponded in FIG. 3 of 1st Embodiment. It is a partial longitudinal cross-sectional view which shows the principal part of 3rd Embodiment of the steam turbine which concerns on this invention, Comprising: The partial longitudinal cross-sectional view corresponded in FIG. 3 of 1st Embodiment. It is a partial longitudinal cross-sectional view which shows the principal part of 4th Embodiment of the steam turbine which concerns on this invention, Comprising: The partial longitudinal cross-sectional view corresponded in FIG. 3 of 1st Embodiment. It is a partial longitudinal cross-sectional view which shows the principal part of 5th Embodiment of the steam turbine which concerns on this invention, Comprising: The partial longitudinal cross-sectional view corresponded in FIG. 3 of 1st Embodiment. It is a fragmentary longitudinal cross-sectional view which shows the principal part of 6th Embodiment of the steam turbine which concerns on this invention, Comprising: The fragmentary longitudinal cross-sectional view corresponded in FIG. 3 of 1st Embodiment. It is a partial longitudinal cross-sectional view which shows the principal part of 7th Embodiment of the steam turbine which concerns on this invention, Comprising: The partial longitudinal cross-sectional view corresponded in FIG. 3 of 1st Embodiment. It is a partial longitudinal cross-sectional view which shows the principal part of 8th Embodiment of the steam turbine which concerns on this invention, Comprising: The partial longitudinal cross-sectional view corresponded in FIG. 3 of 1st Embodiment. It is a fragmentary longitudinal cross-sectional view which shows the principal part of 9th Embodiment of the steam turbine which concerns on this invention, Comprising: The partial longitudinal cross-sectional view corresponded in FIG. 3 of 1st Embodiment.

  Hereinafter, an embodiment of a steam turbine according to the present invention will be described with reference to the drawings. Here, the same or similar parts are denoted by common reference numerals, and redundant description is omitted.

[First Embodiment]
FIG. 1 is a partial longitudinal sectional view showing a main part of a first embodiment of a steam turbine according to the present invention, and is a partial longitudinal sectional view showing an enlarged portion I of FIG. FIG. 2 is a partial vertical cross-sectional view showing the main part of the first embodiment. FIG. 3 is a partial vertical cross-sectional view showing the main part of the first embodiment, and is a partial vertical cross-sectional view showing the portion III of FIG. 1 in an enlarged manner. FIG. 4 is a partial vertical sectional view showing the main part of the first embodiment, and is a partial vertical sectional view showing the IV part of FIG. 2 in an enlarged manner. FIG. 5 is a partial vertical cross-sectional view showing the main part of the first embodiment, and is a partial vertical cross-sectional view showing the V part of FIG. 2 in an enlarged manner.

  This steam turbine is a multistage axial turbine having a double casing structure, and includes an outer casing 101, an inner casing 102 and a ground casing 202 disposed inside as a stationary part. ing. The outside of the external compartment 101 is exposed to the atmosphere. Inside the inner casing 102 and the ground casing 202, the turbine rotor 50 is disposed with the rotation axis horizontal. In the turbine rotor 50, a plurality of stages of moving blades 51 are arranged in the axial direction, and a turbine nozzle 302 is arranged on the upstream side of the moving blades 51 of each stage.

  The turbine nozzle 302 includes a stationary blade portion 303 in which a plurality of stationary blades are arranged in the circumferential direction, an outer annular portion 304 outside the stationary blade portion 303, and an inner annular portion 305 inside the stationary blade portion 303. It has.

  The outer casing 101, the inner casing 102, the ground casing 202, and the turbine nozzle 302 are all stationary members, but are not fixed to each other in order to allow escape of thermal expansion. And the seal | sticker part is formed in each part which these stationary members adjoin. Hereinafter, the seal structure of each part will be described.

(Seal part between external compartment and internal compartment)
First, a seal portion between the external compartment 101 and the internal compartment 102 will be described with reference to FIGS. 1, 2, and 3. A first partition wall 11 and a second partition wall 12 are formed outside the inner casing 102, and an annular space formed by the outer casing 101 and the inner casing 102 is formed into the first partition wall 11 and the second partition wall 102. Two partition walls 12 partition the first space 13, the second space 14, and the third space 15.

  A first fitting groove 17 extending in an annular shape that accepts the outer peripheral portion 16 of the first partition wall 11 is formed at a position where the outer casing 101 faces the outer peripheral portion 16 of the first partition wall 11. The space between the outer peripheral portion 16 of the first partition 11 and the first fitting groove 17 is not fixed to each other, and is slightly movable during assembly.

  Similarly, a second fitting groove 19 extending in an annular shape for receiving the outer peripheral portion 18 of the second partition wall 12 is formed at a position where the outer casing 101 faces the outer peripheral portion 18 of the second partition wall 12. Thus, the outer peripheral portion 18 of the second partition wall 12 and the second fitting groove 19 are not fixed to each other but are opposed to each other with a gap.

  Within the second fitting groove 19, a seal member 30 that extends in an annular shape and can swing in the radial direction is arranged between the outside of the outer peripheral portion 18 of the second partition wall 12 and the bottom portion of the second fitting groove 19. ing. A seal member accommodation groove 31 for accommodating a part of the seal member 30 is formed on the outer peripheral portion 18 of the second partition wall 12 over the entire circumference of the rotation circumference. A wide portion 32 is formed at the base of the seal member 30, a narrow portion 33 is formed at a position close to the bottom of the second fitting groove 19, and a second fitting groove 19 is formed at the tip of the narrow portion 33. A fin portion 34 protruding toward the bottom is formed. The fin portions 34 are in the form of an annular plate, and in the illustrated example, two fins 34 are arranged side by side in the direction of the rotation axis with a space therebetween.

  The seal member accommodation groove 31 has a wide portion and a narrow portion corresponding to the wide portion 32 and the narrow portion 33 of the seal member 30, and the seal member 30 can swing in the rotational radius direction. It is configured not to come out of the groove 31.

  An elastic member 35 such as a spring is disposed at the bottom of the seal member receiving groove 31 and presses the seal member 30 outward in the rotational radial direction, that is, toward the bottom of the second fitting groove 19. Is pressed against the bottom of the second fitting groove 19.

  During the operation of the steam turbine, steam is introduced into the outer casing 101 and the inner casing 102, and the pressure in the first space 13, the second space 14, and the third space 15 is changed to the first space 13. It is the highest in the interior, the lowest in the third space 15, and an intermediate height in the second space 14. Due to such a pressure difference, the inner casing 102 is pressed relative to the outer casing 101 in the direction of the rotation axis and to the left in FIGS. 1 and 2. At this time, the portions near the second space 14 are pressed against each other on the outer peripheral portion 16 of the first partition wall 11 and the first fitting groove 17, and the first space 13 and the first space 13 are pressed by the “steam joint”. A seal portion (first seal portion) 21 between the two spaces 14 is formed.

  On the other hand, a seal member 30 is interposed between the outer peripheral portion 18 of the second partition wall 12 and the second fitting groove 19, so that a seal portion between the second space 14 and the third space 15 ( A second seal portion 22 is formed.

  In particular, in the second seal portion 22, the elastic member 35 presses the seal member 30 against the bottom of the second fitting groove 19, so that steam leakage can be suppressed. Furthermore, since the fin part 34 protrudes, the contact with the sealing member 30 and the bottom face of the fitting groove 19 in the second seal part 22 can be maintained. The flow rate of the steam leaking through the tip of the portion 34 can be suppressed.

  In this way, not only the first seal portion 21 by the steam joint but also the second seal portion 22 prevents the steam leakage between the external compartment 101 and the internal compartment 102 by the action of the seal member 30. Can be suppressed.

(Seal part between external compartment and ground compartment)
Next, a seal portion between the external compartment 101 and the ground compartment 202 will be described with reference to FIGS.

  In the structure shown in FIG. 4, a first space 213, a second space 214, and a third space 215 are formed in an annular shape by the outer casing 101 and the ground casing 202 disposed inside thereof. Yes.

  An annular first fitting groove 40 is formed in the ground casing 202, and a first protrusion 41 is formed in the outer casing 101 so as to fit into the first fitting groove 40.

  Further, an annular second fitting groove 42 is formed in the outer casing 101, and a second protrusion 43 is formed in the ground casing 202 so as to fit into the second fitting groove 42. .

  Further, a seal member accommodation groove 231 is formed at a position facing the external compartment 101 near the second protrusion 43 of the ground compartment 202. The seal member 230 and the elastic member 235 are disposed in the seal member accommodation groove 231. The configurations of the seal member accommodation groove 231, the seal member 230, and the elastic member 235 are respectively the seal member accommodation groove 31, the seal member 30, and the elastic member 35 in the second seal portion 22 between the external compartment and the internal compartment. It is the same as (FIG. 3).

  Similar to the seal portion between the external compartment and the internal compartment described above, steam is introduced into the external compartment 101 and the ground compartment 202 during the operation of the steam turbine, and the first space 213 and the second space are introduced. 214, the pressure in the third space 215 is the highest in the first space 213 and the lowest in the third space 215. Due to such a pressure difference, the ground casing 202 is pressed relative to the outer casing 101 in the direction of the rotation axis and to the left in FIGS.

  At this time, between the first fitting groove 40 of the ground casing 202 and the first protrusion 41 of the outer casing 101, the first space 213 and the second space 214 are connected by the “steam joint”. An intermediate seal portion (first seal portion) 221 is formed.

  On the other hand, since the elastic member 235 presses the seal member 230 toward the outer side in the rotational radius direction and toward the inner surface of the outer casing 101, the seal portion between the second space 214 and the third space 215 ( A second seal portion 222 is formed.

  Thereby, steam leakage between the external compartment 101 and the ground compartment 202 can be suppressed based on the same principle as the seal portion between the external compartment and the internal compartment described above.

(The seal between the internal casing and the turbine nozzle)
Next, a seal portion between the internal casing 102 and the turbine nozzle 302 will be described with reference to FIGS. 2 and 5.

  In the structure shown in FIG. 5, a first space 313, a second space 314, and a third space 315 are formed by the internal casing 102 and the turbine nozzle 302. In this configuration, the pressure during operation of the steam turbine is higher in the first space 313 than in the second space 314. The pressure in the third space 315 may be higher or lower than the pressure in the first space 313 and the pressure in the second space 314 depending on the operation state of the steam turbine.

  In addition, although the turbine nozzle is arrange | positioned for every paragraph, it demonstrates paying attention only to the turbine nozzle 302 of the 1st paragraph here.

  An annular first protrusion 45 that protrudes inward in the rotational radius direction is formed in the inner casing 102. Further, a facing surface 46 of the outer annular portion 304 of the turbine nozzle 302 is formed at a position facing the first projecting portion 45 in the rotation axis direction. During the steam turbine operation, the pressure in the first space 313 is higher than the pressure in the second space 314, so that the facing surface 46 of the turbine nozzle 302 is pressed against the first protrusion 45. As a result, a seal portion (first seal portion) 321 between the first space 313 and the second space 314 is formed by the “steam joint”.

  On the other hand, a second seal portion 322 that partitions the first space 313 and the third space 315 is formed between the inner casing 102 and the inner annular portion 305 of the turbine nozzle 302. It has the same structure as the second seal portion 222 (FIG. 4) in the seal portion between the passenger compartment and the ground compartment. That is, the seal member accommodation groove 331 is formed in the inner periphery of the inner casing 102 at a position where the inner casing 102 faces the cylindrical outer surface of the inner annular portion 305 of the turbine nozzle 302. A seal member 330 and an elastic member 335 are disposed in the seal member accommodation groove 331. The configurations of the seal member accommodation groove 331, the seal member 330, and the elastic member 335 are respectively the seal member accommodation groove 31, the seal member 30, and the elastic member 35 (see FIG. 3) in the seal portion between the external compartment and the internal compartment. It is the same.

  With such a configuration, the elastic member 335 presses the seal member 330 inward in the rotational radial direction against the cylindrical outer surface of the inner annular portion 305 of the turbine nozzle 302, so the first space 313 and the third space A seal part (second seal part) 322 between the space 315 is formed.

[Second Embodiment]
FIG. 6 is a partial longitudinal sectional view showing a main part of a second embodiment of the steam turbine according to the present invention, and is a partial longitudinal sectional view corresponding to FIG. 3 of the first embodiment.

  A seal member accommodation groove 431 is formed at the bottom of the second fitting groove 19 similar to the second fitting groove 19 of the external casing 101 in the first embodiment (FIG. 3). A seal member 430 and an elastic member 435 are disposed in the seal member accommodation groove 431. The seal member accommodation groove 431, the seal member 430, and the elastic member 435 have the same structure as the seal member accommodation groove 31, the seal member 30, and the elastic member 35 of the first embodiment (FIG. 3), respectively. The groove 31, the seal member 30, and the elastic member 35 are disposed so that the relationship between the inner side and the outer side in the rotational radius direction is reversed. A fin portion 434 is formed at the distal end of the seal member 430, and the distal end of the fin portion 434 is pressed against the outer peripheral portion of the outer peripheral portion 18 of the second partition wall 12 by the elastic member 435.

  According to this embodiment, the amount of steam leakage can be reduced as in the first embodiment.

  Here, the second seal portion 22 between the external compartment and the internal compartment of the first embodiment has been described as being replaced with the configuration as shown in FIG. 6, but the structure similar to FIG. The present invention can also be applied to the second seal portion 222 between the vehicle compartment and the ground vehicle compartment and the second seal portion 322 between the internal compartment and the turbine nozzle.

[Third Embodiment]
FIG. 7 is a partial longitudinal sectional view showing a main part of a second embodiment of the steam turbine according to the present invention, and is a partial longitudinal sectional view corresponding to FIG. 3 of the first embodiment.

  This embodiment includes the seal member accommodation groove 31, the seal member 30, and the elastic member 35 in the first embodiment (FIG. 3), and the seal member accommodation groove 431, the seal member 430, and the second embodiment (FIG. 6). The elastic member 435 is combined. The seal member 30 and the seal member 430 are arranged side by side with an interval in the rotation axis direction.

  According to this embodiment, since the two seal members 30 and 430 are arranged in series on the upstream side and the downstream side, the amount of steam leakage can be reduced as compared with the first or second embodiment.

  The arrangement of the two seal members 30 and 430 may be reversed on the upstream side and the downstream side. Three or more seal members may be arranged. Furthermore, the same structure as FIG. 7 can be applied to the second seal portion 222 between the internal compartment and the ground compartment and the second seal portion 322 between the internal compartment and the turbine nozzle.

[Fourth Embodiment]
FIG. 8 is a partial vertical cross-sectional view showing a main part of a fourth embodiment of the steam turbine according to the present invention, and is a partial vertical cross-sectional view corresponding to FIG. 3 of the first embodiment.

  This embodiment is a modification of the first embodiment, and a plurality of implantation fins 508 are provided on the outer peripheral portion 18 of the second partition wall 12 of the external casing 101 in place of the seal member 30 of the first embodiment. Have been implanted. The implantation fin 508 has an annular plate shape extending along a plane perpendicular to the rotation axis, and has a tip projecting toward the bottom of the second fitting groove 19. In the example shown in the figure, there are three implantation fins 508, and they are arranged at intervals in the axial direction.

  According to this embodiment, the tip of the implantation fin 508 can be brought into contact with the bottom of the second fitting groove 19 to reduce the amount of steam leakage from this portion. In addition, since the plurality of implantation fins 508 are arranged in series on the upstream side and the downstream side, the amount of leakage can be further reduced.

  The number of implantation fins 508 is not limited to three, but may be one, two, or four or more. Here, the second seal portion 22 between the external compartment and the internal compartment of the first embodiment has been described as being replaced with the configuration as shown in FIG. 8, but the structure similar to FIG. The present invention can also be applied to the second seal portion 222 between the vehicle compartment and the ground vehicle compartment and the second seal portion 322 between the internal compartment and the turbine nozzle.

[Fifth Embodiment]
FIG. 9 is a partial longitudinal sectional view showing a main part of a fifth embodiment of the steam turbine according to the present invention, and is a partial longitudinal sectional view corresponding to FIG. 3 of the first embodiment.

  This embodiment is a modification of the fourth embodiment, and is implanted at the bottom of the second fitting groove 19 similar to the second fitting groove 19 of the external compartment 101 in the fourth embodiment (FIG. 8). Fins 608 are implanted. The implantation fin 608 has an annular plate shape similar to that of the implantation fin 508 of the fourth embodiment, but is implanted in the bottom of the second fitting groove 19, and the tip of the implantation fin 608 is located in the external casing 101. It extends toward the outer peripheral portion 18 of the second partition wall 12 and is pressed against the outer peripheral portion of the outer peripheral portion 18 of the second partition wall 12.

  According to this embodiment, similarly to the fourth embodiment, the amount of steam leakage can be reduced.

  The number of implantation fins 608 is arbitrary. Here, the second seal portion 22 between the external compartment and the internal compartment of the fourth embodiment has been described as being replaced with the configuration as shown in FIG. 9, but the structure similar to FIG. The present invention can also be applied to the second seal portion 222 between the vehicle compartment and the ground vehicle compartment and the second seal portion 322 between the internal compartment and the turbine nozzle.

[Sixth Embodiment]
FIG. 10 is a partial vertical cross-sectional view showing a main part of a sixth embodiment of the steam turbine according to the present invention, which is a partial vertical cross-sectional view corresponding to FIG. 3 of the first embodiment.

  In this embodiment, the implantation fin 508 in the fourth embodiment (FIG. 8) and the implantation fin 608 in the fifth embodiment (FIG. 9) are combined. In any case, the implantation fins 508 and the implantation fins 608 extending along a plane perpendicular to the rotation axis are arranged alternately in the rotation axis direction and spaced apart from each other.

  According to this embodiment, since the implantation fins 508 extending from the inside to the outside and the implantation fins 509 extending from the outside to the inside are arranged alternately and spaced apart from each other, the fourth or fifth The amount of steam leakage can be reduced compared to the embodiment.

  The structure similar to that shown in FIG. 10 can also be applied to the second seal portion 222 between the internal compartment and the ground compartment and the second seal portion 322 between the internal compartment and the turbine nozzle.

[Seventh Embodiment]
FIG. 11 is a partial longitudinal sectional view showing a main part of a seventh embodiment of the steam turbine according to the present invention, and is a partial longitudinal sectional view corresponding to FIG. 3 of the first embodiment.

  This embodiment is a modification of the first embodiment, and instead of the seal member 30 (FIG. 3) of the first embodiment, an annular plate-like seal member 708 extending along a plane perpendicular to the rotation axis. It has. A seal member receiving groove 710 is formed on the outer peripheral portion 18 of the second partition wall 12, and a seal member receiving groove 711 is formed on the bottom portion of the second fitting groove 19. The seal member receiving grooves 710 and 711 are arranged to face each other in the rotational radius direction. The inner peripheral portion of the seal member 708 is in the seal member receiving groove 710, the outer peripheral portion of the seal member 708 is in the seal member receiving groove 711, and the seal member 708 can be slightly swung in the rotation axis direction and the radial direction. Has been placed.

  When the steam turbine is operating, the pressure in the second space 14 is higher than the pressure in the third space 15, so that the seal member 708 is pushed toward the third space 15 as shown in FIG. A seal is formed between the member receiving groove 710 and the seal member receiving groove 711. Thereby, the vapor | steam leakage in this part can be suppressed.

  Here, since it is difficult to dispose the annular plate-shaped sealing member 708 formed integrally from the beginning at the position shown in FIG. 11, in practice, it is divided in advance into a plurality (for example, two) in the circumferential direction. The annular plate-shaped seal members 708 may be arranged adjacent to each other in the circumferential direction to form an annular plate-shaped seal member 708.

  Here, the second seal portion 22 between the external compartment and the internal compartment of the first embodiment has been described as being replaced with the configuration as shown in FIG. 11, but the structure similar to FIG. The present invention can also be applied to the second seal portion 222 between the vehicle compartment and the ground vehicle compartment and the second seal portion 322 between the internal compartment and the turbine nozzle.

[Eighth Embodiment]
FIG. 12 is a partial longitudinal sectional view showing a main part of an eighth embodiment of the steam turbine according to the present invention, which is a partial longitudinal sectional view corresponding to FIG. 3 of the first embodiment.

  This embodiment is a modification of the first embodiment. Similar to the first embodiment, the second partition 12 is located at a position where the outer casing 101 faces the outer peripheral portion 18 of the second partition 12. A second fitting groove 19 extending in an annular shape for receiving the outer circumferential portion 18 is formed, and the gap between the outer circumferential portion 18 of the second partition wall 12 and the second fitting groove 19 is not fixed to each other. And facing each other.

  In this embodiment, a groove 801 extending in the rotational circumferential direction is formed on the outer peripheral portion 18 of the second partition wall 12, and is rotated from the center of the bottom of the second fitting groove 19 so as to be inserted into the groove 801. A protrusion 802 extending in the circumferential direction is formed. A gasket 808 extending in the rotational circumferential direction is disposed at the bottom of the groove 801. The gasket 808 is of a relatively flexible material and structure that can be plastically deformed when the steam turbine is assembled.

  In this embodiment, when assembling the steam turbine, the gasket 808 is crushed, whereby the gap at the outer peripheral portion 18 of the second partition wall 12 during assembly can be reduced without increasing manufacturing accuracy. Thereby, the leakage of steam can be suppressed.

  Here, the second seal portion 22 between the external compartment and the internal compartment of the first embodiment has been described as being replaced with the configuration as shown in FIG. 12, but the structure similar to FIG. The present invention can also be applied to the second seal portion 222 between the vehicle compartment and the ground vehicle compartment and the second seal portion 322 between the internal compartment and the turbine nozzle.

[Ninth Embodiment]
FIG. 13 is a partial longitudinal sectional view showing a main part of a ninth embodiment of the steam turbine according to the present invention, which is a partial longitudinal sectional view corresponding to FIG. 3 of the first embodiment.

  This embodiment is a modification of the first embodiment. Similar to the first embodiment, the second partition 12 is located at a position where the outer casing 101 faces the outer peripheral portion 18 of the second partition 12. A second fitting groove 19 extending in an annular shape for receiving the outer circumferential portion 18 is formed, and the gap between the outer circumferential portion 18 of the second partition wall 12 and the second fitting groove 19 is not fixed to each other. And facing each other.

  In this embodiment, a sealing agent 908 is filled in the gap between the second fitting groove 19 and the second partition wall 12. The sealant 908 is, for example, grease and is a viscous material, and maintains a viscosity that does not flow out due to a pressure difference between the second space 14 and the third space 15 during operation of the steam turbine. is there.

  According to this embodiment, the leakage of steam at the outer peripheral portion of the second partition wall 12 can be suppressed.

  Here, the second seal portion 22 between the external compartment and the internal compartment of the first embodiment has been described as being replaced with the configuration as shown in FIG. 13, but the structure similar to FIG. The present invention can also be applied to the second seal portion 222 between the vehicle compartment and the ground vehicle compartment and the second seal portion 322 between the internal compartment and the turbine nozzle.

[Other Embodiments]
Each embodiment described above is merely an example, and the present invention is not limited thereto.

  For example, it is not necessary to apply the seal mechanism according to the present invention to all of the stationary seal portions shown in FIG. 2, and it is also possible to apply to some of them. Moreover, you may change and combine the characteristic of the structure of said each embodiment for every seal | sticker part. Furthermore, the seal mechanism according to the present invention can be applied to a stationary seal portion other than the seal portion shown in FIG.

DESCRIPTION OF SYMBOLS 11 ... 1st partition, 12 ... 2nd partition, 13 ... 1st space, 14 ... 2nd space, 15 ... 3rd space, 16 ... Outer peripheral part, 17 ... 1st fitting groove, 18 ... Outer peripheral part, 19 ... second fitting groove, 21 ... seal part (first seal part), 22 ... second seal part, 30 ... seal member, 31 ... seal member accommodating groove, 32 ... wide part, 33 ... Narrow part, 34 ... fin part, 35 ... elastic member, 40 ... first fitting groove, 41 ... first projection part, 42 ... second fitting groove, 43 ... second projection part, 50 ... turbine Rotor, 51 ... Rotor blade, 101 ... External casing (stationary member), 102 ... Internal casing (stationary member), 202 ... Ground casing (stationary member), 213 ... First space, 214 ... Second space 215: third space 230: seal member 231: seal member receiving groove 235: elastic member 3 2 ... turbine nozzle (stationary member), 303 ... stationary blade part, 304 ... outer ring part, 305 ... inner ring part, 313 ... first space, 314 ... second space, 315 ... third space, 330: Sealing member, 331: Sealing member receiving groove, 335: Elastic member, 430 ... Sealing member, 431 ... Sealing member receiving groove, 434 ... Fin part, 435 ... Elastic member, 508 ... Implanting fin, 608 ... Implanting fin, 708 ... Sealing member, 710 ... Sealing member receiving groove, 711 ... Sealing member receiving groove, 801 ... Groove, 802 ... Projection, 808 ... Gasket, 908 ... Sealing agent

Claims (8)

The first, second, and third spaces having different pressures, the first seal portion that partitions between the first and second spaces, and the second that partitions between the second and third spaces A steam turbine having first and second stationary members that are not secured to each other to form a seal portion,
The first seal portion is configured such that the first and second stationary members are pressed against each other due to a difference in pressure in the first and second spaces and sealed.
A seal member is disposed in the second seal portion in a gap between the first stationary member and the second stationary member;
A steam turbine characterized by In the first seal portion, the first and second stationary members are pressed against each other in the rotation axis direction,
2. The steam turbine according to claim 1, wherein in the second seal portion, the first and second stationary members are configured to face each other in a rotational radius direction. The first stationary member is formed with a fitting groove that is recessed in the rotational radial direction at the second seal portion and extends along the rotational circumferential direction.
The second stationary member is formed with a protrusion that is inserted into a fitting groove formed in the first stationary member and extends along the circumferential direction of rotation.
3. The steam according to claim 1, wherein the seal member is disposed in the fitting groove so as to be positioned between a bottom portion of the fitting groove and a tip of the protruding portion. Turbine.   4. The seal member according to claim 1, wherein the seal member is configured to be pressed against at least one of the first and second stationary members by an elastic force. 5. Steam turbine. In the first seal portion, the first and second stationary members are pressed against each other in the rotation axis direction,
The seal member includes an annular plate-like portion extending along a plane perpendicular to the rotation axis;
The steam turbine according to any one of claims 1 to 4, wherein:   The seal member is plastically deformable when the first and second stationary members are assembled, and is adjusted so that the gap between the second seal portions is narrowed by plastic deformation of the seal member. The steam turbine according to any one of claims 1 to 3, wherein:   The first and second stationary members are any combination of a combination of a turbine outer casing and a turbine inner casing, a combination of a turbine casing and a ground casing, and a combination of a turbine casing and a turbine nozzle. The steam turbine according to any one of claims 1 to 6, wherein the steam turbine is. The first, second, and third spaces having different pressures, the first seal portion that partitions between the first and second spaces, and the second that partitions between the second and third spaces A stationary portion seal structure of a steam turbine having first and second stationary members that are not fixed to each other, and forming a seal portion,
The first seal portion is configured such that the first and second stationary members are pressed against each other due to a difference in pressure in the first and second spaces and sealed.
A seal member is disposed in the second seal portion in a gap between the first stationary member and the second stationary member;
Steam turbine stationary part seal structure characterized by

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