WO2014115706A1

WO2014115706A1 - Seal mechanism and rotating machine provided with seal mechanism

Info

Publication number: WO2014115706A1
Application number: PCT/JP2014/051067
Authority: WO
Inventors: 松本　和幸; 博神吉; 真成飯野; 哲也原田
Original assignee: 三菱重工業株式会社
Priority date: 2013-01-23
Filing date: 2014-01-21
Publication date: 2014-07-31

Abstract

Provided is a rotating machine comprising a seal mechanism (2) having the following: a plurality of moving blades extending in the radial direction of a rotation shaft, with intervals therebetween in the circumferential direction; a casing that encloses the moving blades from the outer circumferential side; and a swirl guide part (170) that is provided on the upstream side of a gap formed between the leading edge of the moving blades and the casing. The swirl guide part (170) has a first guide surface (171) that extends along the flow direction of a swirl flow (SL), and a second guide surface (172) that is continuous with the first guide surface (171) and curves in the radial direction.

Description

SEALING MECHANISM AND ROTARY MACHINE HAVING SEALING MECHANISM

The present invention relates to a sealing mechanism such as a steam turbine and a gas turbine, and a rotary machine including the sealing mechanism. This application claims priority based on Japanese Patent Application No. 2013-010084 filed in Japan on January 23, 2013 and Japanese Patent Application No. 2013-012425 filed in Japan on January 25, 2013. And the contents thereof are incorporated herein.

In a rotating machine such as a steam turbine or a gas turbine, a non-contact type sealing mechanism such as a labyrinth seal is used to prevent a working fluid such as steam from leaking through a gap formed between the stationary member and the rotating member. It is used.
Specifically, the labyrinth seal has a seal member such as a seal fin extending toward the moving blade on the inner periphery of the casing that forms the outer shell of the rotating machine, and a step-shaped shroud provided at the tip of the moving blade. (For example, refer to Patent Document 1).

JP 2006-104952 A

In recent years, there are cases in which self-excited vibration such as low-frequency vibration occurs in rotating machines.
The cause of this self-excited vibration is that a flow (swirl flow) having a strong circumferential velocity component (swirl component, swirl component) passing through the stationary blade passes between the seal fins of the labyrinth seal. One of the causes is considered to form an uneven pressure distribution in the circumferential direction in the cavity. From such a background, a structure for reducing and attenuating the circumferential component (swirl component) of the flow leaking from the main flow to the labyrinth seal is desired for the sealing mechanism of the rotary machine.

As such a structure, as in the apparatus described in Patent Document 1, a structure is known in which the surface of the guide vane is oriented in the circumferential direction (direction in which the swirl flow is received). However, in this structure, the swirling flow of the leaked steam may cause a disturbance in the guide vanes and periodically excite adjacent cascades.

The present invention provides a sealing mechanism that can reduce the swirling component of the swirling flow of the leaked steam, which causes self-excited vibration such as low-frequency vibration of the rotating machine, and a rotating machine including the sealing mechanism.

Also, the present invention provides a seal mechanism that can reduce the generation of periodic excitation force while reducing the swirling component of the steam of the rotary machine, and a rotary machine including the seal mechanism.

According to the first aspect of the present invention, the sealing mechanism includes a rotating shaft, a plurality of moving blades extending in the radial direction of the rotating shaft and spaced apart in the circumferential direction, and the moving blades. A casing that surrounds from the outer peripheral side, and a swirl guide portion provided on the upstream side of a gap formed between the tip of the rotor blade and the casing, the swirl guide portion being along the flow direction of the swirl flow And a second guide surface curved in the radial direction continuously to the first guide surface.

According to the above configuration, the swirl guide unit can guide the swirl flow in the radial direction by the second guide surface after guiding the swirling flow by the first guide surface so as to maintain the flow direction. Thereby, since the component along the circumferential direction of the swirl flow is weakened, the swirl component of the swirl flow can be reduced.

In the sealing mechanism, the second guide surface of the swirl guide may be curved radially outward.

According to the above configuration, the second guide surface curved toward the radially outer peripheral side guides the swirling flow flowing from the radially inner peripheral side to the radially outer peripheral side, thereby causing the swirling flow to be in a direction opposite to the rotational direction. The swirl component of the swirl flow can be reduced by turning.

In the sealing mechanism, the second guide surface of the swirl guide may be curved radially inward.

According to the above configuration, the second guide surface curved toward the radially inner peripheral side guides the swirling flow flowing from the radially inner peripheral side to the radially inner peripheral side, thereby further reducing the leaked steam. Can do.

In the sealing mechanism, the swirl guide portions may be connected to each other by a ring-shaped member having a uniform cross-sectional shape in the circumferential direction.
According to the said structure, the vapor | steam which a swirl guide part leaks can further be reduced.

According to the second aspect of the present invention, the seal mechanism includes a rotating shaft, a plurality of moving blades extending in a radial direction of the rotating shaft and spaced apart in the circumferential direction, and the moving blade. A casing that surrounds from the outer periphery side, and a swirl guide portion provided on the upstream side of a gap formed between the tip of the rotor blade and the casing, and the swirl guide portion has a cross-sectional shape that is uniform in the circumferential direction. It has such a ring-shaped member.

According to the above configuration, the ring-shaped member extending in the circumferential direction increases the wetting area between the swirling flow and the swirl guide that circulates upstream of the gap, and friction is generated between the swirling flow and the swirl guide. Therefore, the swirl component of the swirl flow can be reduced.

In the sealing mechanism, the ring-shaped member may be a plate member having a main surface orthogonal to the axial direction of the rotating shaft.

According to the above configuration, since the swirl guide portion has a shape along the circulation direction of the swirling flow, the occurrence of disturbance on the upstream side of the gap can be suppressed.

In the sealing mechanism, the ring-shaped member may have a zigzag shape in which the cross-sectional shape extends in the radial direction.

According to the above configuration, the wetting area between the swirl flow and the swirl guide portion is further increased, so that the swirl component can be further reduced.

In the sealing mechanism, the swirl guide portion includes a support member that connects the surface of the ring-shaped member opposite to the gap and the casing and a plurality of support members along the circumferential direction. The support member may have a guide surface that guides the swirling flow in the radial direction.

According to the above configuration, the component along the circumferential direction of the swirling flow is weakened by the guide surface, so that the swirling component can be reduced.

According to a third aspect of the present invention, a rotary machine includes the sealing mechanism.

According to the above-described sealing mechanism and the rotary machine including the sealing mechanism, the swirl guide portion guides the swirling flow so that the flow direction is maintained by the first guide surface, and then guides the radial direction by the second guide surface. Can do. Thereby, since the component along the circumferential direction of the swirl flow is weakened, the swirl component of the swirl flow can be reduced.

In addition, because the ring-shaped member extending in the circumferential direction increases the wetting area between the swirling flow and the swirl guide portion that circulates upstream of the gap, friction occurs between the swirling flow and the swirl guide portion. The swirling component of the swirling flow can be reduced.

It is a sectional view showing a schematic structure of a steam turbine provided with a seal mechanism concerning a first embodiment of the present invention. It is a principal part expanded sectional view of a steam turbine provided with the sealing mechanism which concerns on 1st embodiment of this invention, and is an expanded sectional view of I of FIG. FIG. 2 is a diagram showing a schematic configuration of a steam turbine provided with a seal mechanism according to the first embodiment of the present invention when viewed from the axial direction, and is a cross-sectional view taken along line AA of FIG. It is detail drawing of the swirl guide plate of the seal mechanism which concerns on 1st embodiment of this invention. FIG. 2 is a diagram showing a schematic configuration of a steam turbine provided with a seal mechanism according to a second embodiment of the present invention when viewed from the axial direction, and is a cross-sectional view taken along line AA of FIG. It is detail drawing of the swirl guide plate of the seal mechanism which concerns on 2nd embodiment of this invention. It is a principal part expanded sectional view of a steam turbine provided with the sealing mechanism which concerns on 3rd embodiment of this invention, and is an expanded sectional view of I of FIG. It is a figure which shows schematic structure which looked at the steam turbine provided with the sealing mechanism which concerns on 3rd embodiment of this invention from the axial direction, and is AA sectional drawing of FIG. It is a principal part expanded sectional view of a steam turbine provided with the seal mechanism which concerns on 4th embodiment, and is an expanded sectional view of I of FIG. FIG. 5 is a diagram showing a schematic configuration of a steam turbine provided with a seal mechanism according to a fourth embodiment when viewed from the axial direction, and is a cross-sectional view taken along line AA of FIG. It is a principal part expanded sectional view of a steam turbine provided with the sealing mechanism which concerns on 5th embodiment, and is an expanded sectional view of I of FIG. It is sectional drawing which shows the modification of the ring-shaped member of 5th embodiment. It is sectional drawing which shows the modification of the ring-shaped member of 5th embodiment. It is detail drawing of the ring-shaped member of the seal mechanism which concerns on 6th embodiment.

(First embodiment)
Hereinafter, a steam turbine which is a rotating machine according to a first embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the steam turbine 1 of the present embodiment is rotatably provided inside a casing 10, a regulating valve 20 that adjusts the amount and pressure of steam S flowing into the casing 10, and the inside of the casing 10. The rotating shaft 30 that transmits power to a machine such as a generator (not shown), the stationary blade 40 held by the casing 10, the moving blade 50 provided on the rotating shaft 30, and the rotating shaft 30 can be rotated about the axis. And a bearing portion 60 to be supported by the main body. Further, the steam turbine 1 of the present embodiment is provided with a seal mechanism 2 for preventing working fluid such as steam from leaking from a gap formed between the tip of the moving blade 50 and the casing 10. Yes.

Casing 10 has an internal space hermetically sealed and a flow path for steam S. A ring-shaped partition plate outer ring (stationary annular body) 11 through which the rotary shaft 30 is inserted is firmly fixed to the inner wall surface of the casing 10.

A plurality of regulating valves 20 are attached to the inside of the casing 10, and each includes a regulating valve chamber 21 into which steam S flows from a boiler (not shown), a valve body 22, and a valve seat 23. The regulating valve 20 is configured such that when the valve body 22 is separated from the valve seat 23, the steam flow path is opened and the steam S flows into the internal space of the casing 10 through the steam chamber 24.

The rotating shaft 30 includes a shaft main body 31 and a plurality of disks 32 extending from the outer periphery of the shaft main body 31 in the radial direction of the rotating shaft 30 (hereinafter simply referred to as the radial direction). The rotating shaft 30 is configured to transmit rotational energy to a machine such as a generator (not shown).
The bearing unit 60 includes a journal bearing device 61 and a thrust bearing device 62, and supports the rotary shaft 30 in a freely rotatable manner.

The stationary blades 40 extend from the casing 10 toward the inner periphery, and constitute a group of annular stationary blades arranged radially so as to surround the periphery of the rotating shaft 30. The stationary blades 40 are respectively held by the partition plate outer ring 11 described above. The inner sides in the radial direction of these stationary blades 40 are connected by a ring-shaped partition plate inner ring 14 through which the rotary shaft 30 is inserted.

The annular stator blade group composed of the plurality of stator blades 40 is formed in six in the axial direction of the rotating shaft 30 (hereinafter simply referred to as the axial direction). The annular stationary blade group converts the pressure energy of the steam S into velocity energy and flows it into the moving blade 50 adjacent on the downstream side.

The moving blade 50 is firmly attached to the outer peripheral portion of the disk 32 included in the rotating shaft 30. A large number of moving blades 50 are arranged radially on the downstream side of each annular stationary blade group to constitute an annular moving blade group.
The annular stator blade group and the annular rotor blade group are configured as a "one stage". That is, the steam turbine 1 is configured in six stages. Among these, the tip part of the moving blade 50 in the last stage is connected with the tip part of the moving blade adjacent to the circumferential direction (henceforth only the circumferential direction) of the rotating shaft 30. The tip of the moving blade 50 in the final stage is called a shroud 51.

As shown in FIG. 2, the shroud 51 includes a step portion 52 (52A to 52C) formed in a step shape with a central portion protruding in the axial direction.

On the downstream side in the axial direction of the partition plate outer ring 11, a cylindrical annular groove 12 is formed which has a diameter increased from the inner peripheral portion of the partition plate outer ring 11 and has the inner peripheral surface of the casing 10 as the bottom portion 13. A shroud 51 is accommodated in the annular groove 12. The bottom portion 13 is opposed to the

step portions

52A, 52B, 52C of the shroud 51 in the radial direction via the gap Gd.

The bottom 13 is provided with three seal fins 17 (17A to 17C) extending in the radial direction toward the shroud 51. The seal fins 17 (17A to 17C) extend from the bottom 13 to the inner periphery toward the step portions 52 (52A to 52C), respectively, and extend in the circumferential direction. These seal fins 17 (17A to 17C) form step portions 52 (52A to 52C) and minute gaps m (mA to mC) in the radial direction.

The dimensions of these minute gaps m (mA to mC) are determined in consideration of the thermal elongation amount of the casing 10 and the rotor blade 50, the centrifugal extension amount of the rotor blade 50, and the like, and the seal fin 17 (17A to 17C) and the rotor blade 50. It is set in a range where and do not touch.

As shown in FIG. 2, the seal mechanism 2 is provided with a plurality of swirl guide plates 170 (swirl guide portions) on the inner periphery of the casing 10 on the downstream side of the stationary blade 40. The swirl guide plate 170 is disposed on the upstream side of the gap Gd formed between the tip of the moving blade 50 and the casing 10, and extends toward the inner peripheral side of the casing 10. The swirl guide plate 170 is fixed by welding. The plurality of swirl guide plates 170 are annularly arranged at positions on the side surface of the partition plate outer ring 11 and facing the inlet side of the seal fins 17. The detailed shape of the swirl guide plate 170 will be described later.

The operation of the steam turbine 1 will be described.
First, when the regulating valve 20 (see FIG. 1) is opened, the steam S flows into the internal space of the casing 10 from a boiler (not shown).

The steam S flowing into the internal space of the casing 10 sequentially passes through the annular stator blade group and the annular rotor blade group in each stage.
While the steam S passes through the stationary blade 40 in each stage of the annular stationary blade group, its circumferential velocity component increases. Most of the steam SM out of the steam S flows between the rotor blades 50, the energy of the steam SM is converted into rotational energy, and rotation is applied to the rotating shaft 30.

On the other hand, a part (for example, about several percent) of the steam S out of the steam S flows out from the stationary blade 40 and then flows into the annular groove 12 while maintaining a strong circumferential component.

As shown in FIG. 4, the swirl guide plate 170 has an L shape. In other words, the swirl guide plate 170 has a shape like a turning vane that turns the flow direction of the fluid flowing in a certain flow direction.

Specifically, the swirl guide plate 170 includes a first guide surface 171 extending along the steam SL forming the swirl flow, and a second guide that curves to the radially outer peripheral side continuously to the first guide surface 171. A surface 172. The first guide surface 171 and the second guide surface 172 are smoothly connected.
In other words, the first guide surface 171 is formed so as to be inclined toward the rotation direction R of the rotary shaft 30 from the radially inner periphery side toward the outer periphery side. The second guide surface 172 is formed so as to incline toward the opposite side of the rotation direction R of the rotary shaft 30 from the radially inner peripheral side toward the outer peripheral side.

The swirl guide plates 170 are, for example, the same number as the stationary blades 40 and arranged at the same pitch as the stationary blades 40. In addition, the pitch of the swirl guide plate 170 does not need to be arranged at the same pitch as the stationary blade 40, and can be arbitrarily set. That is, the number of swirl guide plates 170 in the circumferential direction can be arbitrarily set, and only one place may be installed at a required place.

According to the steam turbine 1 including the seal mechanism 2 of the first embodiment, the swirl guide plate 170 guides the swirl flow by the first guide surface 171 so as to maintain the flow direction, and then by the second guide surface 172. The swirl flow can be turned in the direction opposite to the rotation direction R by guiding it to the radially outer peripheral side. Thereby, the swirling component of the swirling flow can be reduced.

(Second embodiment)
Hereinafter, the steam turbine which is a rotary machine of 2nd embodiment of this invention is demonstrated based on drawing. In addition, in 2nd embodiment, it describes centering around difference with 1st embodiment mentioned above, The description is abbreviate | omitted about the same part.
As shown in FIGS. 5 and 6, the swirl guide plate 170 </ b> B of the second embodiment is continuous with the first guide surface 171 </ b> B extending along the steam SL forming the swirl flow and the first guide surface 171. And a second guide surface 172B that curves toward the radially inner peripheral side. The first guide surface 171B and the second guide surface 172B are smoothly connected.

In other words, the first guide surface 171B is formed to be inclined toward the rotation direction R of the rotary shaft 30 from the radially inner periphery side toward the outer periphery side. The second guide surface 172B is formed so as to incline toward the opposite side to the rotation direction R of the rotary shaft 30 from the radially inner peripheral side toward the outer peripheral side.
Furthermore, the swirl guide plates 170B of the second embodiment are connected to each other. Specifically, the first guide surface 171B of the swirl guide plate 170B on the first circumferential side is connected to the second guide surface 172B of the swirl guide plate 170B on the second circumferential side.

According to the second embodiment, the swirl guide plate 170B guides the swirl flow by the first guide surface 171B so as to maintain the flow direction thereof, and then guides it to the radially inner peripheral side by the second guide surface 172B. can do. Thereby, since the component along the circumferential direction of the swirl flow is weakened, the swirl component of the swirl flow can be reduced.

Further, the second guide surface 172B that curves toward the radially inner peripheral side guides the swirling flow that flows from the radially inner peripheral side to the radially inner peripheral side, whereby the leaked steam can be further reduced.
Furthermore, since the swirl guide plates 170B are connected to each other, the leaked steam can be further reduced.

(Third embodiment)
Hereinafter, the steam turbine which is a rotary machine of 3rd embodiment of this invention is demonstrated based on drawing. In the third embodiment, the differences from the first embodiment described above will be mainly described, and the description of the same parts will be omitted.

As shown in FIGS. 7 and 8, the swirl guide plate 170C of the third embodiment is connected to the guide plate body 173 having the same shape as the swirl guide plate of the first embodiment, and the guide plate body 173. And a ring-shaped member 174 extending in the circumferential direction.
The ring-shaped member 174 is a ring-shaped plate member having a surface along the radial direction, and is connected to the axial end portion of the guide plate main body 173.

According to the third embodiment, by providing the ring-shaped member 174, all the steam SL that has flowed into the flow path formed by the swirl guide plate 170C from the radially inner side passes through this flow path. For this reason, the steam SL is reliably turned in the direction of the second guide surface 172, and the circumferential direction component of the steam SL can be effectively reduced.

(Fourth embodiment)
Hereinafter, the steam turbine which is a rotary machine of 4th embodiment of this invention is demonstrated based on drawing. In the fourth embodiment, the differences from the first embodiment described above will be mainly described, and the description of the same parts will be omitted.
As shown in FIG. 9, the seal mechanism 2 is provided with a swirl guide portion 270 having a ring-shaped member 271 on the inner periphery of the casing 10 on the downstream side of the stationary blade 40. The swirl guide portion 270 is installed on the upstream side of the gap Gd formed between the tip of the rotor blade 50 and the casing.
The ring-shaped member 271 is an annular plate member extending in the circumferential direction in the space upstream of the gap Gd. The ring-shaped member 271 has a uniform cross-sectional shape over the circumferential direction. In other words, the ring-shaped member 271 is a disk-shaped member having a main surface orthogonal to the axial direction of the rotating shaft 30.
The ring-shaped member 271 is provided at a substantially intermediate position between the first axial surface of the partition plate outer ring 11 and the second axial surface of the shroud 51. The outer peripheral end of the ring-shaped member 271 is separated from the casing 10.

The ring-shaped member 271 is supported by a plurality of support members 272 provided along the circumferential direction. The support member 272 has a rod shape, and is provided so as to connect the casing 10 to the surface of the ring-shaped member 271 opposite to the gap Gd.
In addition, the installation location of the support member 272 is not limited to a location as shown in FIG. For example, the support member 272 may be configured to support the outer peripheral end of the ring-shaped member 271 from the radially outer peripheral side of the casing 10. That is, the ring-shaped member 271 may be supported by the support member 272 provided on the bottom portion 13 of the annular groove 12.

Here, the operation of the steam turbine 1 will be described.
First, when the regulating valve 20 (see FIG. 1) is opened, the steam S flows into the internal space of the casing 10 from a boiler (not shown).

The steam S flowing into the internal space of the casing 10 sequentially passes through the annular stator blade group and the annular rotor blade group in each stage.
The steam S increases in the circumferential velocity component while passing through the stationary blade 40 in the annular stationary blade group of each stage. Most of the steam SM out of the steam S flows between the rotor blades 50, and the energy of the steam SM is converted into rotational energy, so that the rotation shaft 30 is rotated.

On the other hand, a part (for example, about several percent) of the steam S out of the steam S flows out from the stationary blade 40 and then flows into the annular groove 12 with the circumferential component increased.

According to the steam turbine 1 including the seal mechanism 2 of the fourth embodiment, the swirl guide portion 270 has the ring-shaped member 271 extending in the circumferential direction, so that the swirl flow SL flowing through the upstream side of the gap Gd Wetting area increases. As a result, since friction is generated between the steam SL and the ring-shaped member 271, a swirling component of the steam SL that is a swirling flow can be reduced.
In other words, the ring-shaped member 271 narrows the flow path width on the upstream side of the gap Gd, that is, increases the wet area, thereby increasing the wall friction acting on the steam SL and reducing the swirl component of the steam SL. it can.

In addition, the ring-shaped member 271 is a plate member whose cross-sectional shape having a main surface orthogonal to the axial direction of the rotary shaft 30 is uniform over the circumferential direction, so that the swirl guide portion 270 has a shape along the circulation direction of the swirling flow. Therefore, the occurrence of disturbance on the upstream side of the gap Gd can be suppressed.

In addition, in 4th embodiment mentioned above, although the structure which provides only one ring-shaped member 271 of the swirl guide part 270 was shown, it does not restrict to this. Two or a plurality of ring-shaped members 271 may be installed apart from each other in the axial direction according to the space margin. Thereby, a wetting area can be increased further and the swirling component of the steam SL can be reduced.

In addition, the ring-shaped member 271 uses not only a flat plate but also a perforated plate (for example, punching metal) in which a plurality of holes are regularly formed on the surface, and allows a certain amount of steam SL to flow in the axial direction. Also good. The plurality of holes need not be regular, and may be irregularly formed. Further, the ring-shaped member 271 may be provided with a plurality of protrusions.

(Fifth embodiment)
Hereinafter, the steam turbine which is a rotary machine of 5th embodiment of this invention is demonstrated based on drawing. In the fifth embodiment, the differences from the fourth embodiment described above will be mainly described, and the description of the same parts will be omitted.
As shown in FIG. 11, the ring-shaped member 271B of the swirl guide portion 270B of the fifth embodiment has a zigzag shape whose cross-sectional shape extends in the radial direction. In other words, the ring-shaped member 271B is formed in a uniform cross-sectional shape over the circumferential direction as in the fourth embodiment, but the surface 273 is inclined toward the first axial side as it goes toward the outer circumferential side in the radial direction. The surface 274 is inclined continuously toward the second axial side as it goes toward the outer peripheral side in the radial direction. That is, the ring-shaped member 271B of the fifth embodiment has an increased surface area compared to the ring-shaped member 271 of the fourth embodiment.

According to the fifth embodiment, since the surface area of the ring-shaped member 271B is increased, the wetted area with the steam SL is further increased, so that the swirl component of the steam SL can be further reduced.

In the fifth embodiment described above, the cross-sectional shape of the ring-shaped member 271B is a zigzag shape. However, the shape is not limited to this as long as the wetted area of the ring-shaped member 271B with the steam SL is increased. Absent.
For example, as shown in FIG. 12, the ring-shaped member 271B may have a sine wave shape. Further, as shown in FIG. 13, the ring-shaped member 271B may have a rectangular wave shape.

(Fifth embodiment)
Hereinafter, the steam turbine which is a rotary machine of 5th embodiment of this invention is demonstrated based on drawing. In the fifth embodiment, the differences from the fourth embodiment described above will be mainly described, and the description of the same parts will be omitted.

As shown in FIG. 14, the support member 272C that supports the ring-shaped member 271C of the swirl guide portion 270C of the fifth embodiment is formed in a plate shape having a guide surface 275 along the flow direction of the steam SL. Specifically, the support member 272C is formed so as to be inclined in the rotation direction R of the rotary shaft 30 from the radially inner periphery side toward the outer periphery side.

According to the fifth embodiment, the guide surface 275 can prevent the occurrence of disturbance while reducing the swirling component of the steam SL.

Note that the shape of the support member 272C of the fifth embodiment described above is not limited to the shape described above. The cross section of the support member 272C may have a wing shape, and after the steam SL is once guided along the flow direction thereof, the shape may be formed along the radial direction.

The technical scope of the present invention is not limited to the above-described embodiments, and includes those in which various modifications are made to the above-described embodiments without departing from the spirit of the present invention. In other words, the configuration described in the above-described embodiment is an example, and can be appropriately changed.
For example, in each embodiment mentioned above, although the steam turbine was demonstrated to an example as a rotary machine, it is not restricted to a steam turbine. Provided between the stator, which is a stationary body, and the rotor, which is a rotating body, seals between high pressure and low pressure, and a swirl flow is formed upstream of the gap formed between the tip of the moving blade and the casing. For example, the rotary machine may be applied to a rotary machine such as a gas turbine or a compressor.

Further, in each of the above-described embodiments, the example in which the swirl guide plate 170 (swirl guide part 270) is installed on the upstream side of the moving blade 50 at the final stage is shown, but the present invention is not limited to this. The swirl guide plate 170 (swirl guide portion 270) may be installed on the upstream side of any moving blade 50.
Moreover, in each embodiment mentioned above, although the case where the steam S was used as a working fluid was demonstrated, if it is a working fluid which can generate | occur | produce a swirl, it will not be restricted to the steam S.
Further, instead of forming the shroud 51 in a step shape, it may be formed in a flat shape.

Also, the ring-shaped member 174 of the third embodiment can be applied to the first embodiment. That is, the swirl guide plate 170 of the first embodiment and the swirl guide plate 170B of the second embodiment may be connected to each other by the ring-shaped member 174 of the third embodiment.

According to the sealing mechanism and the rotary machine including the sealing mechanism, the swirl guide portion can guide the swirl flow in the radial direction by the second guide surface after guiding the swirling flow so as to maintain the flow direction thereof by the first guide surface. it can. Thereby, since the component along the circumferential direction of the swirl flow is weakened, the swirl component of the swirl flow can be reduced. Further, according to this rotary machine, the ring-shaped member extending in the circumferential direction increases the wetted area between the swirling flow and the swirl guide that circulates on the upstream side of the gap, and thus between the swirling flow and the swirl guide. Since the friction is generated, the swirl component of the swirling flow can be reduced.

1 Steam turbine (rotary machine)
DESCRIPTION OF SYMBOLS 2 Seal mechanism 10 Casing 11 Partition plate outer ring 12 Annular groove 13 Bottom 14 Partition plate inner ring 17 Seal fin 20 Adjustment valve 21 Adjustment valve chamber 22 Valve body 23 Valve seat 24 Steam chamber 30 Rotating shaft 31 Axis main body 32 Disc 40 Stator blade 50 Movement Blade 51 Shroud 52 Step unit 60 Bearing unit 61 Journal bearing device 62

Thrust bearing device

170, 170B, 170C, 270, 270B, 270C Swirl guide plate (swirl guide unit)
171, 171 B

First guide surface

172, 172 B Second guide surface 173

Guide plate body

174, 271, 271 B, 271 C Ring-shaped

member

272, 272

C Support member

273, 274 Inclined surface 275 Guide surface SL Steam (swirl flow)

Claims

A rotation axis;
A plurality of rotor blades extending in the radial direction of the rotating shaft and provided with a plurality of intervals in the circumferential direction;
A casing surrounding the rotor blade from the outer peripheral side;
A swirl guide provided on the upstream side of a gap formed between the tip of the rotor blade and the casing,
The sealing mechanism in which the swirl guide portion includes a first guide surface extending along a circulation direction of the swirl flow, and a second guide surface curved in the radial direction continuously to the first guide surface.
The sealing mechanism according to claim 1,
The seal mechanism in which the second guide surface of the swirl guide portion is curved radially outward.
The sealing mechanism according to claim 1,
The sealing mechanism in which the second guide surface of the swirl guide portion is curved radially inward.
The sealing mechanism according to claim 3,
The swirl guide portions are seal mechanisms that are connected to each other by a ring-shaped member having a uniform cross-sectional shape in the circumferential direction.
A rotation axis;
A plurality of rotor blades extending in the radial direction of the rotating shaft and provided with a plurality of intervals in the circumferential direction;
A casing surrounding the rotor blade from the outer peripheral side;
A swirl guide provided on the upstream side of a gap formed between the tip of the rotor blade and the casing,
The sealing mechanism in which the swirl guide portion has a ring-shaped member having a uniform cross-sectional shape in the circumferential direction.
The sealing mechanism according to claim 5,
The ring-shaped member is a sealing mechanism that is a plate member having a main surface orthogonal to the axial direction of the rotating shaft.
The sealing mechanism according to claim 5,
The ring-shaped member is a sealing mechanism in which the cross-sectional shape is formed in a zigzag shape extending in the radial direction.
The seal mechanism according to any one of claims 5 to 7,
The swirl guide unit has a support member that is connected to a surface of the ring-shaped member opposite to the gap and the casing, and a plurality of support members are provided along the circumferential direction.
The support member is a seal mechanism having a guide surface for guiding a swirling flow in the radial direction.
A rotary machine comprising the sealing mechanism according to any one of claims 1 to 8.