JP6138617B2 - Rotating machine seal structure and rotating machine - Google Patents

Description

  The present invention relates to a rotary machine seal structure and a rotary machine, and more particularly to a seal structure installed between a rotary part and a stationary part in a rotary machine such as a steam turbine to prevent leakage.

  In the steam turbine, in order to use steam efficiently, the rotating part and the rotating part are arranged so as to minimize the leakage of steam from the clearance provided between the rotating part and the fixed part (for example, between the rotor and the stationary blade). It is required to improve the performance of the sealing device provided between the fixed portion. In order to meet the demand for leakage reduction, it has been widely used to provide a labyrinth seal device having a seal fin (labyrinth seal) between a rotating part such as a rotor and a fixed part such as a stationary blade.

  In such a labyrinth seal device, for example, as described in Patent Document 1, the labyrinth seal can be moved in the radial direction, and at the time of start-up that easily causes contact with the rotating body, the labyrinth seal is moved away from the rotating body and the tip of the labyrinth seal In the steady operation state, the labyrinth seal is moved closer to the rotating body so that the clearance at the tip of the labyrinth seal is made as small as possible to prevent leakage loss in the steady operation state, and the labyrinth seal itself Techniques for preventing wear have also been proposed.

  In Patent Document 1, the labyrinth seal is composed of a plurality of arc-shaped seal segments so that the labyrinth seal can be moved in the radial direction. And these seal segments are urged | biased in the direction (radial direction outward) which keeps a labyrinth seal away from a rotary body by the elastic non-porous member arrange | positioned between adjacent seal segments. Further, a pressurizing chamber is formed on the outer peripheral surface side of the seal segment, and the upstream steam is supplied to the pressurizing chamber. At the time of startup, since the steam supplied to the pressurizing chamber is not at a high pressure, the labyrinth seal is kept spaced from the rotating body by the force of the elastic non-porous member. During steady operation, steam is at a higher pressure than at startup, so the inside of the pressurized chamber is in a high pressure state, and the force in the direction of the rotating body applied to the seal segment overcomes the urging force of the elastic non-porous member, and the seal segment rotates. It moves in a direction approaching the body, and a small clearance is established between the rotating body and the labyrinth seal.

  Further, in Patent Document 1, the elastic non-porous member disposed between the seal segments adjacent in the circumferential direction generates a force for pushing the adjacent seal segments apart in the circumferential direction, and in the circumferential direction. Provides a seal between adjacent seal segments and minimizes leakage between them.

JP 2000-154877 A

  Adjacent seal segments (seal pieces) can each move in the radial direction, but when the seal segments move in the radial direction, the circumferential clearance between the seal segments simultaneously changes. Normally, when the seal fin or seal segment is closest to the rotating body, the circumferential gap between the seal segments is eliminated to prevent leakage from the circumferential gap, and when the seal segment moves away from the rotating body, the gap between the seal segments is eliminated. Is configured to be large. As a result, a sufficient leakage prevention function can be obtained in the steady operation state in which the seal segment is closest to the rotating body.

  However, when the seal segment moves away from the rotating body, a gap between the seal segments is opened, so that the amount of leakage from the circumferential gap increases. When the amount of leakage increases, the leaked steam from the circumferential gap enters between the seal fin tip and the rotating body, and the pressure on the seal fin tip surface increases. Since the pressure on the tip surface of the seal fin acts against the pressure inside the pressurizing chamber, even if the inside of the pressurizing chamber is in a high pressure state, the pushing force of the seal segment is reduced, and the pressure in the radial direction of the seal segment is reduced. Unlike the setting, the movement timing becomes unstable.

  In Patent Document 2, an elastic member installed between adjacent seal segments is a non-porous member, thereby generating a force that pushes the seal segments apart in the circumferential direction, and from the circumferential gap between the seal segments. Prevents leakage. Thereby, even when the seal segment is moved away from the rotating body and a circumferential clearance between the seal segments is opened, a stable operation can be performed.

  However, when the elastic non-porous member described in Patent Document 1 is used as the elastic member, the movement of the seal segment is limited to be small because the extension stroke of the elastic member is smaller than that of a normal plate spring or coil spring. For this reason, it is difficult to increase the circumferential clearance.

  Normally, when starting a steam turbine, in order to prevent contact due to the difference in thermal expansion of the rotor, casing, etc., steam at a relatively low temperature is first introduced, and then the steam temperature and pressure are gradually increased to make it as uniform as possible. Care is taken to obtain thermal deformation. However, even if the steam temperature and pressure are gradually increased, the rotor, seal fin, seal segment (seal piece) and casing cannot be kept at a uniform temperature, resulting in a non-uniform temperature distribution and non-uniform thermal expansion in each part. Produce.

  Since the heat capacity of the seal segment is smaller than that of the casing, the seal segment tends to have a higher temperature than the casing temperature, and the circumferential length of the seal segment increases due to thermal expansion of the casing. At this time, when the circumferential clearance is set small, the circumferential length of the seal segment increases even if the seal segment and the seal fin are brought closer to the rotating body. Prior to reaching, the circumferential end of the seal segment contacts and stops radial movement. For this reason, the clearance of the seal fin tip cannot be reduced to a set value. The gap at the tip of the seal fin is fixed with a large gap, a sufficient leakage prevention function cannot be obtained, and the steam turbine efficiency is lowered.

  Furthermore, since the circumferential length of the seal segment has increased, it cannot be pressed against the positioning flange at the set radial position. For this reason, the aggregate | assembly of the seal segment which contacted and became ring shape will be in an unstable state without being fixed. When the assembly of seal segments moves violently, the sliding part between the pressurizing chamber and the seal segment wears out, and when the wear becomes severe and leakage from the sliding part increases, the seal segment moves in the radial direction. May become unstable and may become inoperable in some cases.

  In addition, when each seal segment operates at a slightly different timing, the seal segment that operates later is narrowed in the circumferential direction because the adjacent seal segment that operated earlier is thermally expanded and the circumferential space is narrowed. The adjacent seal segment becomes an obstacle and cannot move in the radial direction. Since the seal segment is kept away from the rotating body and a large portion is generated with the gap at the tip of the seal fin being opened, a sufficient leakage prevention function cannot be obtained, and the steam turbine efficiency is lowered.

  The present invention relates to a seal structure for a rotary machine in which a seal fin or a seal fin opposing portion can be moved in a radial direction according to an operating state of the rotary machine by using a working fluid pressure and a spring force of the rotary machine. Even if the seal substrate) is thermally expanded, it is possible to stably move the radial direction of the seal fin or the seal fin opposing portion, and to reduce leakage from the gap at the circumferential end of the seal piece. It is an object of the present invention to provide a seal structure for a rotating machine that can perform the above-described operation.

  In order to solve the above-described problems, the present invention provides a seal piece that is divided in the circumferential direction and includes a seal fin or a seal fin-opposing portion in accordance with the operating state of the rotating machine using the working fluid pressure and the spring force of the rotating machine. In a rotary machine seal structure that is movable in the radial direction, a gap formed between adjacent seal pieces has an opening on the leaking steam inflow side, and the opening expands adjacent to the leaking steam inflow pressure. A seal member that is elastically deformed so as to close a gap between the seal pieces is provided.

  According to the present invention, even if the seal piece is thermally expanded, the radial movement of the seal fin or the seal fin opposing portion can be stably performed, and leakage is caused from the gap at the circumferential end of the seal piece. Can be reduced.

  Problems, configurations, and effects other than those described above will be clarified by the following description of embodiments.

It is a block diagram of the steam turbine which concerns on embodiment of this invention. It is a figure explaining the embodiment of the present invention by the X section enlarged view of FIG. It is a figure explaining the sealing member used for the labyrinth sealing device which concerns on embodiment of this invention, and installed between sealing pieces. It is the schematic of the labyrinth sealing device seen from the rotor axial direction of FIG. 2A, and is a figure which shows the state which the seal | sticker piece separated from the rotor. It is a figure explaining the state where the seal piece approached the rotor in the labyrinth seal device concerning the embodiment of the present invention. It is the schematic of the labyrinth sealing device seen from the rotor axial direction of FIG. 4, and is a figure which shows the state which the seal piece adjoined to the rotor. It is the schematic of the labyrinth sealing device which concerns on other embodiment of this invention, Comprising: It is a figure which shows embodiment which installed the groove | channel which hold | maintains the sealing member installed between seal pieces. It is the schematic of the labyrinth sealing device which concerns on other embodiment of this invention, Comprising: It is a figure which shows embodiment which installed multiple sealing members installed between seal pieces. It is the schematic of the labyrinth sealing device which concerns on other embodiment of this invention, Comprising: It is a figure which shows embodiment which has distribute | arranged multiple sealing fins on the sealing substrate of the sealing piece. It is the schematic of the labyrinth sealing device which concerns on other embodiment of this invention, Comprising: It is a figure which shows embodiment which applied this invention to the staggered type labyrinth sealing device. It is the schematic of the labyrinth sealing device which concerns on other embodiment of this invention, Comprising: It is a figure which shows embodiment which applied this invention to the seal structure of the front-end | tip part of a moving blade. It is a figure which shows the labyrinth sealing apparatus which concerns on other embodiment of this invention, Comprising: It is a figure which shows embodiment which applied this invention to the labyrinth sealing apparatus which has arrange | positioned the free-cutting spacer to both a sealing board | substrate and a rotor.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as appropriate.

  First, a steam turbine as an example of a rotating machine to which the present invention is applied will be described with reference to FIG. The steam turbine basically has a vertically symmetrical structure, and FIG. 1 schematically shows the upper half. As shown in FIG. 1, the steam turbine 2 includes a rotor 2a in which a plurality of moving blades 2b are fixed in the circumferential direction, a casing 2d that encloses the rotor 2a and the moving blades 2b, and a nozzle diaphragm outer ring 3b in the casing 2d. And a stationary blade 2c provided. A nozzle diaphragm inner ring 3a is provided inside the stationary blade 2c. The moving blade 2b and the stationary blade 2c are alternately arranged with respect to the axial direction of the rotor 2a to form a turbine stage. In the steam turbine 2, the rotor 2a, the moving blade 2b, and the like are rotating parts, and the casing 2d, the stationary blade 2c, the nozzle diaphragm inner ring 3a, the nozzle diaphragm outer ring 3b, and the like are fixed parts.

  When the steam St generated in the boiler flows into the casing 2d, the steam St expands while alternately passing between the stationary blade 2c and the moving blade 2b, and rotates the rotor 2a. Then, the steam that has passed through the rotor blade 2b provided on the most downstream side of the rotor 2a, that is, the rotor blade 2b in the final stage is exhausted to the outside of the casing 2d.

  In the steam turbine 2 configured in this way, the rotor 2a and the rotor blades 2b, which are rotating parts, are fixed parts in order to efficiently transmit the driving force to the rotor blades 2b with the steam St flowing inside the casing 2d. It is required to improve the sealing performance between the casing 2d and the stationary blade 2c and to suppress the amount of steam (leakage steam) leaking from the clearance formed between the rotating part and the fixed part.

  For example, a clearance is provided between the rotor 2a and the nozzle diaphragm inner ring 3a provided at the inner tip of the stationary blade 2c to allow rotational movement of the rotor 2a. This clearance also causes leakage steam of the steam St flowing into the stationary blade 2c. In order to suppress the amount of the leaked steam, a seal device such as a labyrinth seal device 3c is generally provided in the vicinity of the rotor 2a of the nozzle diaphragm inner ring 3a, and the clearance between the rotor 2a and the stationary blade 2c is reduced to improve the sealing performance. Improves and suppresses the amount of leaking steam.

  In addition to this, in the steam turbine 2, such a sealing device is provided between the tip of the moving blade 2b and the casing 2d, or between the rotor 2a and the ground portion 80, and the present invention relates to these seals. Applicable to equipment.

  The labyrinth seal device of the present embodiment is configured such that the gap between the seal fin and the seal fin facing portion can be changed. That is, in this embodiment, a pressure receiving portion that receives the vapor pressure and a spring portion that opposes the vapor pressure are provided. When the vapor pressure is low, a gap between the seal fin and the seal fin facing portion is opened, and the vapor pressure is reduced. When it is high, the gap between the seal fin and the seal fin facing portion is configured to be closed, and at the time of start-up in which contact is likely to occur, the seal fin and the seal fin facing portion are kept away from each other. And the seal fin facing portion are brought close to each other, so that wear of the seal fin at the time of start-up is prevented, and leakage loss in a steady operation state is reduced.

  Next, the labyrinth seal device of the present embodiment will be described in detail with reference to FIGS. 2A to 5. FIG. 2A is an enlarged view of a portion X in FIG. 1 and shows an example of a labyrinth seal device. In FIG. 2A, the outline of the upper half is shown as in FIG. FIG. 2A is a high-low type labyrinth seal device, and is a diagram illustrating an example of an embodiment of the present invention.

  As shown in FIG. 2A, a high-low labyrinth seal device 3c includes a plurality of seal fins 2a1 formed on the outer peripheral portion of a rotor (rotating portion) 2a, a plurality of high portions 3c3, and a low portion 3c4 formed therebetween. And a seal substrate (seal piece) 3c1 fitted to a holder 4 formed on the nozzle diaphragm inner ring (fixed part) 3a so as to be movable in the radial direction. Yes. The high portion 3c3 and the low portion 3c4 of the seal substrate 3c1 are disposed to face the seal fin 2a1. In this embodiment, the fixed portion is provided with the seal fin facing portion via the seal substrate 3c1, and the rotating portion is provided with the seal fin.

  The holder 4 accommodates the outer peripheral side (holding body 3c2) of the seal substrate (seal piece) 3c-1, and is a space where steam St is introduced from the steam passage port 5 (a pressure receiving part that receives the steam pressure of the upstream steam). ) Is provided. The pushing stop position in the radial direction of the seal substrate is determined by the flange 44 provided on the holder 4 and the protrusion of the holding body 3c2.

  FIG. 3 shows a schematic view seen from the rotor axial direction of FIG. 2A. As shown in FIG. 3, the arc-shaped seal substrate 3c1 is divided into a plurality (six in this embodiment) in the circumferential direction. As shown in FIG. 2A, a spring (elastic body) 6 that applies a force that pushes the adjacent seal substrate in the circumferential direction is installed on the circumferential dividing surface of each seal substrate 3c1. The spring 6 is fixedly provided on the circumferentially divided surface of one seal substrate 3c1, and is provided so as to be in contact with the circumferentially divided surface of the other seal substrate 3c1. In this embodiment, one spring 6 is provided on the circumferential dividing surface, but a plurality of springs may be provided. Moreover, when providing a some spring between one circumferential direction division | segmentation surfaces, you may make it provide by changing a fixed side. Moreover, the spring 6 is embedded in the circumferential dividing surface so that it can be replaced. When the pressure of the steam St is low by appropriately selecting the spring 6 and installing it to oppose the pressure of the steam St, between the seal fin 2a1 and the high part 3c3 and the low part 3c4 of the seal substrate 3c1 When the gap is opened and the pressure of the steam St is high, the gap between the seal fin 2a1 and the high portion 3c3 and the low portion 3c4 becomes small, and the opening degree of the gap can be adjusted by the degree of the pressure of the steam St. It becomes.

  As shown in FIGS. 2A and 3, a seal member 7 is provided separately from the spring 6 on the circumferential dividing surface of the seal substrate 3 c 1. The seal member 7 has an opening on the leaking steam inflow side, and the opening expands due to the leaking steam inflow pressure and is elastically deformed so as to close a gap between adjacent seal substrates (seal pieces).

  FIG. 2B shows a configuration example of the seal member 7. In the configuration example shown in FIG. 2B, the seal member 7 is configured by a thin plate, and when leaked steam flows in from the opening side, the width of the opening of the seal member 7 is widened by the vapor pressure (right side of the drawing). From left to right). This makes it possible to close the gap between the circumferential end surfaces of the adjacent seal substrates. The seal member 7 has a conformability to the opening due to elastic deformation and a strength that does not cause plastic deformation due to steam inflow pressure. For example, it is made of stainless steel such as SUS403 steel and has a thickness of about 0.1 to 0.3 mm. The seal member 7 is fixed to the circumferential dividing surface of the seal substrate 3c1 by brazing or welding. Or you may fix by inserting the edge part of a sealing member in the groove | channel formed in the circumferential direction division surface.

  Next, the operation of the labyrinth seal device of this embodiment will be described with reference to FIGS. 2A and 3 to 5.

  2A and 3 show a case where the pressure of the steam St introduced from the steam passage port 5 is low, and the movable portion 3c2 and the seal substrate 3c1 move away from the rotor 2a. For example, the steam turbine is in a starting stage.

  The spring 6 is installed on the dividing surface to apply a force that pushes the seal substrate (seal piece) 3c1 in the circumferential direction. For this reason, the seal substrate 3c1 receives a force outward in the radial direction so that the circumferential gap length at the attachment position of the spring 6 on the split surface is increased. The seal substrate 3c1 configured to be movable in the radial direction moves in a direction away from the rotor 2a side.

  When the pressure of the steam St introduced from the steam passage port 5 is low, the seal substrate by the spring 6 installed on the dividing surface is generated by the force to bring the seal substrate 3c1 close to the rotor 2a side due to the pressure of the steam St. The force that pushes 3c1 outward in the radial direction is larger, and the sealing substrate 3c1 configured to be movable in the radial direction is held at a position far from the rotor 2a side.

  At this time, a circumferential clearance is widened on the circumferential dividing surface of the seal substrate 3c1. In addition to the spring 6, a seal member 7 having an opening on the leakage steam inflow side and closing the gap is installed on the circumferential dividing surface. When leaking steam flows in the seal member 7, the width of the opening is widened by the steam pressure, the gap on the circumferential end surface of the seal substrate (seal piece) 3c1 is closed, and the steam leak in the axial direction of the rotor 2a is prevented. It can be stopped.

  4 and 5 show a case where the pressure of the steam St introduced from the steam passage port 5 is high, and the movable portion 3c2 and the seal substrate 3c1 are closest to the rotor 2a. For example, the rated operation state of the steam turbine is shown.

  As shown in FIGS. 4 and 5, when the pressure of the steam St introduced from the steam passage port 5 is high, the force to bring the seal substrate 3c1 close to the rotor 2a side due to the pressure of the steam St is divided. It becomes larger than the force which pushes the sealing board 3c1 by the spring 6 installed on the surface outward in the radial direction. The seal substrate 3c1 configured to be movable in the radial direction moves so as to be close to the rotor side. At this time, the seal substrate 3c1 moves so as to approach the rotor side until the protruding portion of the holding body 3c2 contacts the positioning flange 44.

  As shown in FIG. 5, even when the seal substrate 3c1 is moved to a specified position, a minute gap is provided on the circumferential end surface of the seal substrate 3c1, and the seal substrate 3c1 is circumferentially moved by thermal expansion. Therefore, it is possible to avoid malfunctions in the radial direction. Furthermore, since the deformable material 7 having an opening on the leakage steam inflow side and closing the gap is provided on the circumferential dividing surface of the seal substrate 3c1, the deformable material 7 is deformed when the leaked steam flows. The width of the opening is widened by the vapor pressure, and the gap in the circumferential end surface of the seal substrate 3c1 is closed, and the vapor leakage in the axial direction of the rotor 2a can be stopped. Since the seal member 7 of the present embodiment has a large gap that can be handled, it is possible to easily set a gap in which the radial movement of the seal substrate due to thermal expansion does not become defective. Further, the seal member 7 is provided separately from the spring 6 and may have a smaller elastic force than the force by which the spring 6 pushes the circumferentially divided surface, so that the movement of the seal substrate 3c1 by the spring 6 is substantially affected. Not give.

  And the clearance gap between the several seal fin 2a1 formed in the outer peripheral part of the rotor 2a, and the high part 3c3 with which the seal board | substrate 3c1 was equipped, and the low part 3c4 becomes small. That is, since the seal substrate 3c1 can move smoothly to the set position, the seal fin 2a1, and the high portion 3c3 and the low portion 3c4 provided in the seal substrate 3c1 form a set gap. As a result, the amount of steam leakage is reduced, and high steam turbine efficiency can be obtained.

  By using the structure of the seal structure of the present embodiment, the gap is opened at a relatively low steam pressure at the initial stage of the steam turbine startup to enable stable startup of the steam turbine, and the gap is reduced during steady operation with a high load steam pressure. Thus, the amount of leaked steam can be minimized and high steam turbine efficiency can be obtained.

  In addition, by using the configuration of the seal structure of the present embodiment, the seal fin is moved away from the rotating body at the time of start-up that easily causes contact with the rotating body. Wear of the seal fin can be prevented, leakage loss in a steady operation state can be minimized, and high steam turbine efficiency can be obtained.

  Furthermore, according to the present embodiment, the gap at the circumferential end of the seal piece is increased to prevent a malfunction in the radial direction due to thermal expansion of the seal piece, and the gap at the circumferential end of the seal piece. Leakage from the air is reduced, and stable operation and stable sealing performance can be ensured.

  Another embodiment of the present invention will be described. FIG. 6 shows an example of another embodiment of the present invention. Unlike the embodiment of FIGS. 2A to 5, the seal member 7 and the groove 9 in which the seal member 7 is installed are arranged on the seal substrate 3c1. It is. The groove 9 functions as a place for storing a part of the seal member 7. According to the present embodiment, the following effects can be obtained in addition to the effects of the above-described embodiments. That is, by providing the groove 9 for installing the seal member 7 and selecting the depth of the groove, a minute gap can be adjusted in a wide range from a very small value to a large value on the circumferential end surface of the seal substrate 3c1. .

  In the present embodiment, the example in which the groove 9 for installing the seal member 7 is arranged on the seal substrate 3c1 to which the seal member 7 is attached has been described. However, the groove 9 that engages (accommodates) the other end of the seal member 7 is described. May be disposed on the surface of the seal substrate 3c1 facing the seal member 7.

  Another embodiment of the present invention will be described. FIG. 7 shows an example of another embodiment of the present invention, which is an example in which a plurality of seal members 7 for closing the gap are arranged on the seal substrate 3c1. According to the present embodiment, the following effects can be obtained in addition to the effects of the embodiments shown in FIGS. 2A to 5 described above. That is, in this embodiment, since a plurality of seal members 7 are installed on the circumferential dividing surface of the seal substrate, it is possible to more completely stop the steam leakage in the axial direction of the rotor 2a.

  Another embodiment of the present invention will be described. FIG. 8 shows an example of another embodiment of the present invention, in which a plurality of seal fins 3c5 are arranged on the seal substrate 3c1. According to this embodiment, the same effects as those of the embodiment shown in FIGS. 2A to 5 can be obtained.

In the above-described embodiment, the case where the present invention is applied to a high-low type labyrinth seal device has been described. However, the present invention can be similarly applied to a staggered-type labyrinth seal device.
There is 3c. The present invention can also be applied to such a staggered labyrinth seal device. A case where the present invention is applied to a staggered labyrinth seal device will be described with reference to FIG.

  As shown in FIG. 9, a seal substrate 3c1 having a plurality of seal fins 3c5 is fitted to the nozzle diaphragm inner ring side 3a so as to be movable in the radial direction. The seal substrate 3c1 is provided with grooves 3c6 at predetermined intervals, and the seal fins 3c5 are caulked and fixed in the grooves 3c6.

  Further, the rotor 2a is also provided with grooves 2a2 at predetermined intervals, and seal fins 2a1 are caulked and fixed in the grooves 2a2.

  The seal fins 3c5 and the seal fins 2a1 are arranged so as to alternately overlap in the axial direction of the rotor 2a.

  When the seal substrate 3c1 moves so as to be close to the rotor 2a side, the gap between the seal fin 3c5 and the rotor 2a is reduced, and the gap between the tip of the seal fin 2a1 and the seal substrate 3c1 is reduced. The amount of leakage becomes small, and high steam turbine efficiency can be obtained.

  According to this embodiment, the same effects as those of the embodiment shown in FIGS. 2A to 5 can be obtained.

  In each of the above-described embodiments, the case where the present invention is applied to the labyrinth seal device 3c provided between the diaphragm inner ring 3a of the stationary blade 2c and the rotor 2a has been described. However, as shown in FIG. In addition, the present invention can be applied to a labyrinth seal device provided in the gland portion 80. FIG. 10 shows an embodiment in which the present invention is applied to a labyrinth seal device provided at the tip of a moving blade (rotating part).

  As shown in FIG. 10, a seal fin 3b1 is provided at the tip of the moving blade (rotating part) 2b, and a plurality of seal fin opposing parts (seal substrate 3c1) are provided on the opposite side (fixed part). The tip of the moving blade 2b is provided with a cover 2g for reducing the clearance with the nozzle diaphragm outer ring 3b (or casing 2d), and a seal fin 3b1 is provided on the cover 2g. The nozzle diaphragm outer ring 3b is provided with a radially movable seal substrate 3c1 formed with a high portion and a low portion so as to face the seal fins 3b1 of the cover 2g. And the spring 6 is installed in the circumferential direction division surface in order to give the force which pushes and opens the sealing substrate 3c1 in the circumferential direction. In addition, a seal member 7 that closes a gap between the circumferential division surfaces of the seal substrate 3c1 is provided. Others are the same as the above-mentioned Example, and detailed description is abbreviate | omitted. Also in this embodiment, the same effects as those of the embodiment shown in FIGS. 2A to 5 can be obtained.

  In addition, the present invention can be applied to a labyrinth seal structure in which a free-cutting spacer such as an abradable material is arranged on a rotor, or a labyrinth seal structure in which a free-cutting spacer such as an abradable material is arranged on a seal substrate. It is. The labyrinth seal structure in which such a free-cutting spacer is arranged is described in Japanese Patent Application Laid-Open No. 2002-228013 and Japanese Patent Application Laid-Open No. 2003-65076. And in such a structure, since a fin is protected at the time of seal fin contact, damage to a seal fin decreases.

  FIG. 11 shows an embodiment in which the present invention is applied to a labyrinth seal device in which free-cutting spacers are arranged on both the seal substrate and the rotor. A free-cutting spacer 8 is disposed on the rotor 2a so as to face the seal fins 3c5 formed on the seal substrate 3c1. A free-cutting spacer 8 is disposed on the seal substrate 3c1 so as to face the seal fins 2a1 formed on the rotor 2a. And the spring 6 is installed in the circumferential direction division | segmentation surface in order to give the force which pushes open the sealing board | substrate 3c1 divided | segmented into the circumferential direction into the circumferential direction. In addition, a seal member 7 that closes a gap between the circumferential division surfaces of the seal substrate 3c1 is provided. Others are the same as the above-mentioned Example, and detailed description is abbreviate | omitted.

  Also in this embodiment, the same effects as those of the embodiment shown in FIGS. 2A to 5 can be obtained. This embodiment can also be applied to the other embodiments described above. For example, a free-cutting spacer is installed on the surface facing the seal fin of the seal substrate 3c1 in the labyrinth seal device provided at the tip of the moving blade 2b shown in FIG.

  A breathable spacer can be used instead of the free-cutting spacer. Examples of a sealing device using a breathable spacer are described in Japanese Patent Application Laid-Open No. 2009-138666 and Japanese Patent Application Laid-Open No. 2010-261351. In such a configuration, the heat generated when the seal fin contacts is cooled, so that the occurrence of vibration due to thermal deformation or thermal bending of the rotor can be suppressed. The same effect can be obtained by applying the present invention to such a configuration.

  Further, in each of the above-described embodiments, the steam turbine is described as an example of the rotating machine, but the present invention can be similarly applied to a gas turbine or the like.

  In addition, this invention is not limited to an above-described Example, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Moreover, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

  2 ... steam turbine, 2a ... rotor (rotating part), 2a1, 3c5 ... seal fins, 2b ... moving blade (rotating part), 2c ... stationary blade (fixed part), 2d ... casing (fixed part), 2g ... cover, 3a ... Nozzle diaphragm inner ring, 3b ... Nozzle diaphragm outer ring, 3c ... Labyrinth seal device, 3c1 ... Seal substrate (seal piece), 4 ... Holder, 44 ... Positioning flange, St ... Steam, 5 ... Steam passage port, 6 ... Spring, 7 ... Seal member, 8 ... Free-cutting spacer (free-cutting spacer having air permeability), 9 ... Groove, 80 ... Gland.

Claims (8)

A rotary machine seal structure provided between a rotary part of a rotary machine and a fixed part located around the rotary part,
A seal substrate provided by being divided in the circumferential direction and provided with seal fins or seal fin facing portions;
A holder for supporting each of the seal substrates movably in the radial direction with respect to the fixed portion, introducing a working fluid of a rotating machine into the interior, and operating the seal substrate to the rotating portion side by a working fluid pressure;
An elastic body that applies a radially outward force to the divided seal substrate;
A seal member fixed to a circumferential dividing surface of the seal substrate, having an opening on the leaking steam inflow side, the opening being expanded by the leaking steam inflow pressure, and a gap formed between the adjacent seal substrates A seal structure for a rotary machine, comprising a seal member that is elastically deformed so as to close the shaft. In claim 1,
The sealing structure for a rotary machine, wherein the elastic body that applies a radially outward force to the divided seal substrate is a spring provided on a circumferential division surface of the seal substrate. In the rotary machine seal structure according to claim 2,
The sealing structure of a rotary machine, wherein the seal substrate is configured such that a gap is set in a circumferential dividing surface of the seal substrate at a position where the seal substrate is closest to the rotating portion. In the rotary machine seal structure according to claim 3,
A seal structure for a rotary machine, wherein a groove for fixing the seal member is provided on a circumferential dividing surface of the seal substrate. In the rotary machine seal structure according to claim 3,
A rotation characterized in that a groove for accommodating the other end of the seal member is provided on a circumferential partition surface of the adjacent seal substrate facing a circumferential partition surface of the seal substrate to which the seal member is fixed. Mechanical seal structure. The seal structure for a rotary machine according to claim 1,
A sealing structure for a rotary machine, wherein a plurality of the sealing members are provided on a circumferential dividing surface of the sealing substrate. A rotary machine having the rotary machine seal structure according to any one of claims 1 to 6,
The rotating machine is a steam turbine;
The rotating part is a rotor;
The fixed portion is a stationary blade fixed to a casing containing the rotating portion or a member integral with the stationary blade,
The rotary machine is characterized in that the seal structure of the rotary machine is provided between the rotor and the stationary blade or a tip portion integral with the stationary blade. A rotary machine having the rotary machine seal structure according to any one of claims 1 to 6,
The rotating machine is a steam turbine;
The rotating part is a moving blade provided in a rotor or a member integral with the moving blade,
The fixed portion is a casing containing the rotating portion or a member fixed to the casing,
The rotary machine is characterized in that the seal structure of the rotary machine is provided between the tip of the moving blade or a member integral with the moving blade and the casing or a member fixed to the casing.

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