阅读说明：本技术 旋转机械及密封部件 (Rotary machine and seal member ) 是由 植田泰彦 福岛久刚 田中健太郎 于 2019-07-16 设计创作，主要内容包括：本发明提供一种旋转机械及密封部件,其具备：壳体(11)；转子(12),旋转自如地支承于壳体(11)内；固定叶片(13),固定于壳体(11)的内周部；转动叶片(14),固定于转子(12)的外周部；及密封装置(15),配置在壳体(11)的内周部与转动叶片(14)的末端部之间,在壳体(11)的内周部设置叶片安装槽(31),并且与叶片安装槽(31)相邻地设置填缝槽(32),将固定叶片(13)的基端部装配于叶片安装槽(31),通过将填缝部件(33)卡止于填缝槽(32)及固定叶片(13)的叶片根部(13a)而将固定叶片(13)固定于壳体(11)的内周部,作为密封装置(15)将密封环(41)装配于壳体(11)的内周部,并由密封环(41)包覆填缝槽(32)的至少一部分。(The present invention provides a rotary machine and a sealing member, comprising: a housing (11); a rotor (12) rotatably supported in the housing (11); a fixed blade (13) fixed to the inner peripheral portion of the housing (11); a rotor blade (14) fixed to the outer peripheral portion of the rotor (12); and a sealing device (15) which is arranged between the inner peripheral part of the housing (11) and the tail end part of the rotating blade (14), wherein the inner peripheral part of the housing (11) is provided with a blade mounting groove (31), a caulking groove (32) is arranged adjacent to the blade mounting groove (31), the base end part of the fixed blade (13) is assembled in the blade mounting groove (31), the caulking part (33) is clamped in the caulking groove (32) and the blade root part (13a) of the fixed blade (13) to fix the fixed blade (13) on the inner peripheral part of the housing (11), the sealing ring (41) is assembled on the inner peripheral part of the housing (11) as the sealing device (15), and at least one part of the caulking groove (32) is covered by the sealing ring (41).)

1. A rotary machine is characterized by comprising:

a housing having a hollow shape;

a rotor rotatably supported in the housing;

a fixed blade fixed to an inner peripheral portion of the housing;

a rotor blade fixed to an outer peripheral portion of the rotor in a staggered manner in an axial direction of the rotor with respect to the stationary blade; and

a sealing device disposed between an inner peripheral portion of the housing and a tip end portion of the rotor blade,

the housing is provided with a mounting recess on an inner peripheral portion thereof, and a caulking recess is provided adjacent to the mounting recess,

the fixed blade is fixed to the inner peripheral portion of the housing by a proximal end portion being fitted to the mounting recess and a caulking member being locked to the caulking recess and the proximal end portion of the fixed blade,

the sealing device has a sealing member fitted to an inner peripheral portion of the housing, the sealing member covering at least a part of the caulking recess.

2. Rotating machine according to claim 1,

the caulking recess is provided further on the upstream side in the fluid flow direction than the mounting recess, and an end portion of the sealing member on the downstream side in the fluid flow direction covers the caulking recess.

3. Rotating machine according to claim 1 or 2,

a predetermined gap is provided between an end of the seal member in a flow direction of the fluid and the fixed blade.

4. Rotating machine according to claim 3,

between the plurality of stages of the fixed blades, a flat surface along the axial direction of the rotor is provided by the seal member.

5. Rotating machine according to claim 4,

the flat surface of the seal member is continuous with the inner peripheral surface of the housing without a step.

6. A seal member disposed between an inner peripheral portion of a casing and a tip end portion of a rotor blade, the seal member comprising:

a mounting portion assembled to an inner peripheral portion of the housing;

a seal portion provided radially inside the mounting portion; and

a plurality of fins projecting radially inward from the seal portion and provided at predetermined intervals in a fluid flow direction,

when the distance between the most upstream fin and the most downstream fin among the plurality of fins is D1, and the distance between the most downstream fin and the downstream end of the sealing portion is D2,

D1X 0.5 < D2.

7. The seal member of claim 6,

if the distance between the upstream end of the seal portion and the most upstream fin is D3,

d3 < D2.

8. The seal member according to claim 6 or 7,

the seal portion has a protruding portion that extends further downstream than a downstream end of the rotor blade in an assembled state of being assembled to an inner peripheral portion of the housing.

9. The seal member of claim 8,

the protruding portion is provided with a cavity radially outward in the assembled state.

10. The seal member according to claim 8 or 9,

the sealing portion is provided with the plurality of fins only at a position upstream of the protruding portion.

Technical Field

The present invention relates to a rotary machine in which a seal device for suppressing fluid leakage is disposed between a stationary side and a rotating side, and a seal member constituting the seal device.

Background

For example, the steam turbine is constituted as follows: the rotor is rotatably supported in a housing by a bearing, and a plurality of stages of rotor blades are fixed to the rotor while a plurality of stages of fixed blades are fixed to the housing. Then, the steam is supplied from the supply port of the casing, passes through the plurality of rotor blades and the stationary blade, thereby driving the rotary rotor via each rotor blade, and is discharged from the discharge port to the outside.

In such a steam turbine, in order to suppress an axial leakage flow of steam between the casing and the tip end portion of the rotor blade, a sealing device is provided between the tip end portion of the rotor blade and the casing. The sealing device is generally adapted for use with labyrinth seals. The labyrinth seal is configured by providing a plurality of sealing fins on the tip end portion of the rotor blade or the inner surface of the casing. A pressure loss is generated by forming a gap between the plurality of sealing fins and the inner surface of the casing or the tip end portion of the rotor blade, and the leakage flow of the steam in the axial direction is suppressed by the pressure loss. As such a sealing device, for example, a sealing device described in patent document 1 below is known.

Prior art documents

Patent document

Patent document 1: japanese Kokai publication Hei 04-093573

Disclosure of Invention

Technical problem to be solved by the invention

In the above steam turbine, the steam flow leaking from the sealing device joins the main flow of the steam passing through the rotating blades or the fixed blades. The main flow of the steam is a flow along the axial direction of the rotor, and the leakage flow of the steam at the tip end of the rotor blade is a flow inclined from the inner peripheral portion of the casing toward the rotor side. In this case, it is important to reduce the mixing loss in the merging portion to suppress the performance degradation by smoothly merging the leakage flow of the steam into the main flow of the steam.

However, the base end portions of the rotor blades, which are positioned radially inward, are fixed to the outer peripheral portion of the rotor, while the base end portions of the stationary blades, which are positioned radially outward, are fixed to the inner peripheral portion of the casing. In this case, the fixed blade is fixed to the housing by fitting the base end portion into a mounting groove formed in the inner peripheral portion of the housing, and then pressing the caulking member into a caulking groove formed between the base end portion of the fixed blade and the mounting groove. The caulking groove is formed on the upstream side in the flow direction of the steam in the stationary blade. Therefore, the steam flow leaking from the sealing device is influenced by the caulking groove to become a longitudinal vortex in the radial direction, and is merged into the main flow of the steam while maintaining a large inclination angle. Then, the leakage flows of the steam interfere with each other when they merge into the main flow of the steam, and the performance is degraded due to an increase in the mixing loss in the merging portion.

The present invention has been made to solve the above-described problems, and an object thereof is to provide a rotary machine and a seal member, which smoothly join a leakage flow of a fluid from a seal device to a main flow of the fluid, thereby reducing a mixing loss in a joining portion and improving performance.

Means for solving the technical problem

A rotary machine according to the present invention for achieving the above object is characterized by comprising: a housing having a hollow shape; a rotor rotatably supported in the housing; a fixed blade fixed to an inner peripheral portion of the housing; a rotor blade fixed to an outer peripheral portion of the rotor in a staggered manner in an axial direction of the rotor with respect to the stationary blade; and a sealing device disposed between an inner peripheral portion of the housing and a tip end portion of the rotor blade, wherein the housing is provided with a mounting recess on an inner peripheral portion thereof, and a caulking recess is provided adjacent to the mounting recess, the fixed blade is fixed to the inner peripheral portion of the housing by a base end portion being fitted to the mounting recess and a caulking member being locked to the caulking recess and the base end portion of the fixed blade, the sealing device includes a sealing member fitted to the inner peripheral portion of the housing, and the sealing member covers at least a part of the caulking recess.

Accordingly, when the fluid is supplied to the inside of the casing, the main flow of the fluid passes through the fixed blades and the rotor blades, and the rotor blades rotate, while a part of the fluid flows between the casing and the tip end portions of the rotor blades, and the sealing device functions to suppress leakage of the fluid. At this time, a part of the fluid leaking from the sealing device joins a main flow of the fluid passing through the fixed blade and the rotating blade. Here, since the caulking recess provided in the inner peripheral portion of the housing is covered with the sealing member, the fluid leaking from the sealing device smoothly merges into the main flow of the fluid without being affected by the caulking recess to form a longitudinal vortex. As a result, the fluid leaking from the sealing device is smoothly merged into the main flow of the fluid, whereby the mixing loss in the merged portion can be reduced to improve the performance.

In the rotary machine according to the present invention, the caulking recess is provided on an upstream side in a fluid flow direction from the mounting recess, and an end portion of the sealing member on a downstream side in the fluid flow direction covers the caulking recess.

Accordingly, since the end portion of the seal member covers the caulking recess, the caulking recess can be appropriately covered with a simple structure.

In the rotary machine according to the present invention, a predetermined gap is provided between an end of the seal member in the fluid flow direction and the stationary blade.

Accordingly, since the predetermined gap is provided between the end portion of the seal member and the fixed blade, the seal member can be prevented from interfering with the peripheral member due to thermal expansion, and deformation of the seal member can be prevented.

In the rotary machine according to the present invention, a flat surface along the axial direction of the rotor is provided by the seal member between the plurality of stages of the fixed blades.

Accordingly, since the flat surface is provided by the seal member, the fluid leaking from the seal device can smoothly flow through the flat surface, and the leakage flow of the fluid can be smoothly merged into the main flow of the fluid.

In the rotary machine according to the present invention, the flat surface of the seal member is continuous with the inner peripheral surface of the housing without any step.

Accordingly, since the flat surface of the seal member is continuous with the inner peripheral surface of the housing without a step, the fluid introduced into the seal device or the fluid leaking from the seal device can smoothly flow through the flat surface and the inner peripheral surface, and the leakage flow of the fluid can smoothly join the main flow of the fluid.

Further, a seal member disposed between an inner peripheral portion of a housing and a tip end portion of a rotor blade, the seal member comprising: a mounting portion assembled to an inner peripheral portion of the housing; a seal portion provided radially inside the mounting portion; and a plurality of fins that protrude radially inward from the seal portion and are provided at predetermined intervals in a fluid flow direction, wherein D1 × 0.5 < D2 is defined as D1 for a distance between an uppermost fin and a lowermost fin among the plurality of fins and D2 for a distance between the lowermost fin and a downstream end of the seal portion.

Accordingly, by smoothly merging the fluid leaking from the seal member into the main flow of the fluid, the mixing loss in the merging portion can be reduced to achieve an improvement in performance.

In the seal member of the present invention, when a distance between an upstream end of the seal portion and the most upstream fin is D3, D3 < D2.

In the seal member according to the present invention, the seal portion has a projection portion that extends further downstream than a downstream end of the rotor blade in an assembled state of the seal portion assembled to the inner peripheral portion of the housing.

In the seal member according to the present invention, the protruding portion is provided with a cavity on a radially outer side in the assembled state.

In the seal member according to the present invention, the plurality of fins are provided only at a position upstream of the protruding portion in the seal portion.

Effects of the invention

According to the rotary machine and the seal member of the present invention, the leakage flow of the fluid from the seal device is smoothly merged into the main flow of the fluid, and the mixing loss in the merged portion is reduced to improve the performance.

Drawings

Fig. 1 is a sectional view showing a mounting portion of a seal device in a steam turbine as a rotary machine according to the present embodiment.

Fig. 2 is a sectional view showing a mounting portion of a seal device according to a modification of the steam turbine of the present embodiment.

Fig. 3 is a schematic view showing a steam turbine according to the present embodiment.

Fig. 4 is a schematic diagram for explaining the structure of the seal member of the present embodiment.

Detailed Description

Hereinafter, preferred embodiments of a rotary machine according to the present invention will be described in detail with reference to the accompanying drawings. The present invention is not limited to the embodiment, and when there are a plurality of embodiments, the present invention also includes an invention configured by combining the respective embodiments.

Fig. 3 is a schematic view showing a steam turbine according to the present embodiment.

In the present embodiment, a steam turbine will be described as an example of the rotary machine according to the present invention. As shown in fig. 3, the steam turbine 10 includes a casing 11, a rotor 12, stationary blades 13, rotor blades 14, and a sealing device 15.

The housing 11 has a hollow shape, and a rotor 12 is disposed inside along a horizontal direction. The rotor 12 is supported by a bearing 20 provided in the housing 11 to be rotatable about the axial center O. A plurality of fixed blades 13 are fixed to the inner circumferential portion of the casing 11 at predetermined intervals along the axial direction a of the rotor 12. A plurality of rotating disks 21 are fixed to the rotor 12 at predetermined intervals along the axial direction a on the outer peripheral portion, and a plurality of rotor blades 14 are fixed to the outer peripheral portion of each rotating disk 21. The fixed blades 13 and the rotor blades 14 are arranged along the radial direction R of the rotor 12 at predetermined intervals in the circumferential direction of the rotor 12, and are alternately arranged along the axial direction a of the rotor 12.

The casing 11 is provided with a steam supply port 22 at one end side in the axial direction a, and the steam supply port 22 communicates with a blade row portion 24 in which the respective stationary blades 13 and the respective rotor blades 14 are arranged through a steam passage 23. The blade row portion 24 communicates with a steam discharge port 26 through an exhaust chamber 25.

Further, the rotor 12 is provided with a seal member 27 between each end in the axial direction a and the housing 11. The seal members 27 are disposed further toward the inner side than the bearings 20, that is, further toward the stationary blade 13 and the rotor blade 14. Further, a seal device 15 is provided between a tip end portion of the rotor blade 14 located outside in the radial direction R and an inner peripheral portion of the housing 11.

Therefore, when the steam S is supplied from the steam supply port 22 to the blade row portion 24 through the steam passage 23, the steam S passes through the plurality of stationary blades 13 and the plurality of rotor blades 14, thereby driving the rotary rotor 12 via the respective rotor blades 14 and driving a generator, not shown, coupled to the rotor 12. Then, the steam S driving the turning vanes 14 is discharged from the steam discharge port 26 through the discharge chamber 25.

Here, the relationship among the casing 11, the stationary blades 13, the rotor blades 14, and the sealing device 15 in the steam turbine 10 will be described in detail. Fig. 1 is a sectional view showing a mounting portion of a seal device in a steam turbine as a rotary machine according to the present embodiment.

As shown in fig. 1, the sealing device 15 is provided between the casing 11 and the tip end portion of the rotor blade 14. The seal device 15 suppresses flow leakage of the steam (fluid) S flowing from the high pressure side H to the low pressure side L along the axial direction a of the rotor 12 between the casing 11 and the tip end portion of the rotor blade 14. Here, the steam S flows in a steam flow direction a1 along the axial direction a from the high pressure side H to the low pressure side L. At this time, the steam S flows so that the main flow passes through the stationary blades 13 and the rotor blades 14, and a part of the steam S flows toward the seal 15 between the casing 11 and the tip end portions of the rotor blades 14, thereby generating leakage steam S1 that leaks from the seal 15.

The base end of the fixed vane 13 located on the outer side in the radial direction R is fixed to the inner peripheral portion of the casing 11, while the base end of the rotor vane 14 located on the inner side in the radial direction R is fixed to the outer peripheral portion of the rotor 12. That is, the casing 11 is provided with the blade mounting groove 31 as a mounting recess continuously along the radial direction R and the circumferential direction on the inner circumferential portion. The housing 11 is provided with a caulking groove 32 as a caulking recess along the radial direction R and the circumferential direction on the inner circumferential portion. The caulking grooves 32 are provided on the upstream side of the blade mounting groove 31 in the steam flow direction a1 so as to communicate with each other at positions adjacent to the blade mounting groove 31.

The blade mounting groove 31 is formed to maintain a predetermined depth in the radial direction R from the inner circumferential surface 11a of the housing 11. The caulking groove 32 is formed from the inner peripheral surface 11a of the housing 11 to maintain a predetermined depth shallower than the blade mounting groove 31 in the radial direction R. The caulking groove 32 includes a1 st groove 32a opened to the inner peripheral surface 11a of the housing 11, a 2 nd groove 32b continuous with the 1 st groove 32a, and a locking groove 32c continuous with the 2 nd groove 32 b. The length in the axial direction a of the 2 nd groove 32b is shorter than the length in the axial direction a of the 1 st groove 32a, and the 2 nd groove 32b is bent at right angles toward the upstream side in the steam flow direction a1 to form a locking groove 32 c.

The fixed blade 13 includes a blade root 13a as a base end portion positioned on the outer side in the radial direction R and a fixed blade body 13b extending from the blade root 13a to the inner side in the radial direction R. The fixed blade 13 has a locking stepped portion 13c formed in the blade root portion 13 a. The caulking member 33 fixes the fixed blade 13 to the blade mounting groove 31. The caulking member 33 includes: an insertion portion 33a which is inserted into the caulking groove 32 and has a length in the axial direction a shorter than the 1 st groove 32a and the 2 nd groove 32b of the caulking groove 32; and a locking part 33b which is bent at a right angle from the insertion part 33a to the upstream side in the steam flowing direction A1.

Accordingly, the blade root 13a of the fixed blade 13 is inserted into the blade mounting groove 31 of the housing 11, and the caulking member 33 is inserted into the caulking groove 32. At this time, the distal end portion of the caulking member 33 is locked to the locking stepped portion 13c in the blade root 13a of the fixed blade 13, and the locking portion 33b is locked to the locking groove 32c of the caulking groove 32. Then, the caulking member 33 is fixed to the housing 11 so as not to fall off by the locking portion 33b being locked to the locking groove 32c of the caulking groove 32, and the fixed blade 13 is fixed to the housing 11 so as not to fall off by the locking stepped portion 13c being locked to the caulking member 33. Further, the caulking member 33 is press-fitted into the caulking groove 32 by a press-fitting jig not shown, and at this time, the locking portion 33b is locked to the locking groove 32c of the caulking groove 32 while being deformed.

The rotor blade 14 has: a blade root (not shown) located radially inward of the base end portion; a rotor blade body 14a extending outward in the radial direction R from the blade root; and a shroud 14b as a tip end portion located outside the rotor blade body 14a in the radial direction R. The rotor blades 14 have blade roots fixed to an outer peripheral portion of the rotor 12 (not shown in fig. 3), and are disposed between the respective stationary blades 13 disposed at predetermined intervals along the axial direction a.

The sealing device 15 has a seal ring 41 as a sealing member fitted on the inner peripheral portion of the housing 11, and is constituted by the seal ring 41 and the shroud 14b of the rotor blade 14. The housing 11 has a T-shaped seal attachment groove 42 formed in an inner peripheral portion thereof. The packing attachment groove 42 includes a1 st groove 42a along the axial direction a, a 2 nd groove 42b that opens the 1 st groove 42a to the inner peripheral surface 11a of the housing 11, and a notch 42c along the axial direction a. The cut portion 42c has only one end portion in the axial direction a (a downstream portion in the steam flow direction a 1) opening toward the stationary blade 13. The packing installation grooves 42 are continuously provided in the circumferential direction of the housing 11.

The seal ring 41 includes an attachment portion 41a, a coupling portion 41b, a seal portion 41c, and a plurality of (3 in the present embodiment) fins 41d and 41 e. The mounting portion 41a has a shape along the axial direction a, and is connected to the sealing portion 41c via a connecting portion 41 b. The seal portion 41c has a shape along the axial direction a, and both end portions extend toward the fixed vane 13. The plurality of fins 41d and 41e extend from the seal portion 41c toward the rotor blade 14. The seal ring 41 is annular in the circumferential direction, and the mounting portion 41a is fitted in the 1 st groove 42a of the seal mounting groove 42 provided in the housing 11, the coupling portion 41b is fitted in the 2 nd groove 42b, and the seal portion 41c is fitted in the notch portion 42 c. The 3 fins 41d and 41e are provided at predetermined intervals along the axial direction a of the seal portion 41c, and the tip end portions thereof extend so as to face the shroud 14b of the rotor blade 14. The number of the fins 41d and 41e is not limited to the above number.

The shroud 14b of the rotor blade 14 is provided with a convex portion 14d on the outer peripheral surface. The projection 14d is provided at an intermediate position in the axial direction a in the shroud 14 b. The 2 fins 41d of the seal ring 41 are provided with a minute gap between the tip end portion and the shroud 14b of the rotor blade 14. The length of the fin 41e of the seal ring 41 is shorter than the length of the fin 41d, and a small gap is provided between the tip end portion and the convex portion 14d of the rotor blade 14. In this case, the inner surface of the seal portion 41c in the seal ring 41 is a flat surface 43 in the axial direction a, and the outer surface of the shroud 14b in the rotor blade 14 is a flat surface 44 in the axial direction a. The flat surface 43 of the seal portion 41c of the seal ring 41 is continuous with the inner peripheral surface 11a of the housing 11 without a step. The protruding portion 14d of the shield 14b may be eliminated, and the lengths of the fins 41d and 41e of the seal ring 41 may be made equal.

The seal ring 41 covers at least a part of the caulking groove 32. The seal ring 41 is disposed such that the seal portion 41c is in close contact with the cut portion 42c of the housing 11 between the plurality of stationary blades 13, and thus the downstream end portion of the seal ring 41 in the steam flow direction a1 of the steam S covers the 1 st groove 32a of the caulking groove 32 from the outside.

In this case, only one end portion in the axial direction a of the seal ring 41 faces the blade root portion 13a of the fixed blade 13, and a predetermined gap G1 is provided between the one end portion in the axial direction a and the blade root portion 13a of the fixed blade 13. The other end of the seal ring 41 faces the end surface of the cutout portion 42c of the housing 11, and a predetermined gap G2 is provided between the other end of the seal ring 41 and the end surface of the cutout portion 42 c. The predetermined gaps G1 and G2 are set in consideration of the ease of assembly of the seal ring 41, the amount of thermal expansion of the seal ring 41 and peripheral components, and the like. When the steam S is supplied to the inside of the casing 11, the stationary blades 13, and the seal ring 41 are heated and thermally expanded. At this time, if the gaps G1 and G2 are not defined, the seal ring 41 may be deformed by coming into contact with the casing 11, the stationary blade 13, or the like, and the sealing performance may be degraded. The seal ring 41 may cover at least a part of the caulking groove 32, but the dimension in the axial direction a of the predetermined gaps G1 and G2 is preferably set to 30% or less of the dimension in the axial direction of the caulking groove 32. Specifically, for example, it is preferably set in a range of more than 0mm and 5mm or less.

The inner surface of the seal portion 41c of the seal ring 41 is a flat surface 43 along the axial direction a, but is not limited to this shape. For example, the shape may be a convex shape or a convex curved shape protruding toward the rotor blade 14 side, or a concave shape or a concave curved shape recessed toward the casing 11 side. The inner surface of the portion of the seal portion 41c of the seal ring 41 covering the caulking groove 32 may be inclined or curved toward the rotor blade 14 (axial center O).

Therefore, when the steam S is supplied to the inside of the casing 11 and the turning vanes 14 are rotated, the steam flows in the steam flow direction a1 from the high pressure side H to the low pressure side L. At this time, the steam S flows so that the main flow passes through the stationary blades 13 and the rotor blades 14, and a part of the steam S flows toward the seal device 15 provided between the casing 11 and the tip end portions of the rotor blades 14. The sealing device 15 suppresses the leakage of the steam S, but a part of the steam S leaks to generate the leakage steam S1. The leakage steam S1 leaked from the sealing device 15 is guided to the inner surface (flat surface 43) of the sealing portion 41c in the seal ring 41 and the front surface of the blade root 13a of the fixed blade 13, flows toward the fixed blade body 13b side, and merges with the main flow of the steam S. Here, since the caulking groove 32 formed in the inner peripheral portion of the housing 11 is covered with the sealing portion 41c of the seal ring 41, the leakage steam S1 does not form a longitudinal vortex under the influence of the caulking groove 32. As a result, the merging angle θ of the leak steam S1 with respect to the main flow of the steam S becomes small, and the leak steam S1 merges smoothly into the main flow of the steam S.

In the above description, the seal ring 41 is provided in all regions between the plurality of stationary blades 13, but the present invention is not limited to this configuration. Fig. 2 is a sectional view showing a mounting portion of a seal device according to a modification of the steam turbine of the present embodiment.

In a modification of the rotary machine of the present embodiment, as shown in fig. 2, the sealing device 50 is provided between the inner peripheral portion of the casing 11 and the tip end portion of the rotor blade 14. The housing 11 is provided with a blade mounting groove 31 and a caulking groove 32 on an inner peripheral portion. The fixed blade 13 has a blade root 13a and a fixed blade body 13b, and a locking stepped portion 13c is formed on the blade root 13 a. The caulking member 33 is a member for fitting the fixed blade 13 to the blade mounting groove 31. Accordingly, the fixed blade 13 is fixed to the housing 11 by the blade root 13a being inserted into the blade mounting groove 31 of the housing 11 and the caulking member 33 being inserted into the caulking groove 32.

The rotor blade 14 includes a blade root (not shown), a rotor blade body 14a, and a shroud 14 b. The sealing device 50 has a seal ring 51 as a sealing member fitted on the inner peripheral portion of the housing 11, and is constituted by the seal ring 51 and the shroud 14b of the rotor blade 14. The housing 11 has a T-shaped seal attachment groove 52 formed in an inner peripheral portion thereof. The packing attachment groove 52 has a1 st groove 52a along the axial direction a and a 2 nd groove 52b that opens the 1 st groove 52a to the inner peripheral surface 11a of the housing 11. The packing installation grooves 52 are continuously provided in the circumferential direction of the housing 11.

The seal ring 51 includes an attachment portion 51a, a coupling portion 51b, a seal portion 51c, and a plurality of (2 in the present embodiment) fins 51 d. The mounting portion 51a has a shape along the axial direction a, and is connected to the sealing portion 51c via the connecting portion 51 b. The seal portion 51c has a shape along the axial direction a, and both end portions extend toward the fixed vane 13. The plurality of fins 51d extend from the seal portion 51c toward the rotor blade 14. The seal ring 51 is annular in the circumferential direction, and the mounting portion 51a is fitted in the 1 st groove 52a of the seal mounting groove 52 provided in the housing 11, and the coupling portion 51b is fitted in the 2 nd groove 52 b. The seal ring 51 is disposed on the inner circumferential surface 11a of the housing 11 between the fixed blades 13 in which the seal portions 51c are disposed at predetermined intervals along the axial direction a. The 2 fins 51d are provided at predetermined intervals along the axial direction a of the seal portion 51c, and the tip end portions thereof extend so as to face the shroud 14b of the rotor blade 14. The number of the fins 51d is not limited to the above number.

The shroud 14b of the rotor blade 14 is provided with fins 14c on the outer peripheral surface. The fin 14c is provided at an intermediate position between the 2 fins 51d of the seal ring 51, and extends so that a tip end portion thereof faces the seal portion 51 c. Each fin 51d of the seal ring 51 has a minute gap set between the tip end portion and the shroud 14b of the rotor blade 14. Further, a minute gap is set between the fin 14c of the rotor blade 14 and the seal portion 51c of the seal ring 51. In this case, the inner surface of the seal portion 51c in the seal ring 51 is a flat surface 53 in the axial direction a, and the outer surface of the shroud 14b in the rotor blade 14 is a flat surface 54 in the axial direction a. The sealing device 50 of the present embodiment is a labyrinth seal, and a pressure loss of the steam S is generated by a minute gap between each fin 51d of the seal ring 51 and the shroud 14b and a minute gap between the fin 14c of the rotor blade 14 and the seal portion 51c, and a leakage flow of the steam S in the axial direction a is suppressed by the pressure loss.

The seal ring 51 covers at least a part of the caulking groove 32. In the seal ring 51, the seal portion 51c is disposed on the inner peripheral surface 11a of the housing 11 between the plurality of fixed blades 13, and therefore the downstream end portion of the seal ring 51 in the steam flow direction a1 of the steam S covers the 1 st groove 32a of the caulking groove 32 from the outside.

In this case, both ends of the seal ring 51 in the axial direction a face the blade root portions 13a of the fixed blades 13, and predetermined gaps G1, G2 are provided between the ends of the seal ring 51 and the blade root portions 13a of the fixed blades 13. The predetermined gaps G1 and G2 are set in consideration of the ease of assembly of the seal ring 51, the amount of thermal expansion of the seal ring 51 and the peripheral members, and the like.

Note that the operation of the modified example of the present embodiment is substantially the same as that of the present embodiment, and therefore, the description thereof is omitted.

Here, a specific configuration of the seal ring (seal member) 41 of the present embodiment will be described. Fig. 4 is a schematic diagram for explaining the structure of the seal member of the present embodiment.

As shown in fig. 4, a seal ring 41 as a seal member is disposed between the inner peripheral portion of the housing 11 and the distal end portion of the rotor blade 14. The seal ring 41 includes: a mounting portion 41a fitted on an inner peripheral portion of the housing 11; a seal portion 41c provided radially inside the mounting portion 41 a; and a plurality of fins 41d, 41e protruding radially inward from the seal portion 41c and provided at predetermined intervals in the flow direction of the steam S.

In the present embodiment, the number of the fins 41d and 41e is 3, and the fins are constituted by the most upstream fin 41d-1 provided on the upstream end (left end in fig. 4) side of the sealing portion 41c, the most downstream fin 41d-2 provided on the downstream end (right end in fig. 4) side of the sealing portion 41c, and the fin 41e between the most upstream fin 41d-1 and the most downstream fin 41 d-2. Further, when the 1 st distance between the most upstream fin 41D-1 and the most downstream fin 41D-2 is D1, and the 2 nd distance between the most downstream fin 41D-2 and the downstream end of the seal portion 41c is D2,

D1X 0.5 < D2 is set.

When the 3 rd distance between the upstream end of the seal portion 41c and the most upstream fin 41D-1 is D3,

d3 < D2 is set.

The lengths D1, D2, and D3 are lengths from the center position in the flow direction of the steam S in the most upstream fin 41D-1 or the most downstream fin 41D-2.

In an assembled state in which the seal portion 41c of the seal ring 41 is assembled to the inner peripheral portion of the housing 11, the seal portion 41c has a protrusion 41f extending downstream of the downstream end 14e of the rotor blade 14 (shroud 14 b). The protruding portion 41f is provided with a caulking groove 32 as a cavity on the radially outer side in the assembled state. The sealing portion 41c is provided with a plurality of fins 41d (41d-1, 41d-2), 41e only at a position upstream of the protruding portion 41 f.

The rotary machine according to the present embodiment includes: a housing 11 having a hollow shape; a rotor 12 rotatably supported in the housing 11; a fixed vane 13 fixed to an inner peripheral portion of the housing 11; rotor blades 14 fixed to the outer peripheral portion of the rotor 12 in a manner shifted from the stationary blades 13 in the axial direction a of the rotor 12; and sealing devices 15, 50 arranged between the inner peripheral portion of the housing 11 and the tip end portion of the rotor blade 14, the inner peripheral portion of the housing 11 being provided with a blade mounting groove 31, and a caulking groove 32 being provided adjacent to the blade mounting groove 31, the base end portion of the fixed blade 13 being fitted to the blade mounting groove 31, the fixed blade 13 being fixed to the inner peripheral portion of the housing 11 by locking the caulking member 33 to the caulking groove 32 and the blade root portion 13a of the fixed blade 13, sealing rings 41, 51 being fitted to the inner peripheral portion of the housing 11 as the sealing devices 15, 50, and at least a part of the caulking groove 32 being covered with the sealing rings 41, 51.

Accordingly, when the leakage steam S1 leaked from the sealing devices 15, 50 joins the main flow of the steam S passing through the stationary blades 13 and the moving blades 14, since the caulking groove 32 is covered by the sealing rings 41, 51, the leakage steam S1 does not form a longitudinal vortex by the influence of the caulking groove 32, and smoothly joins the main flow of the steam S. As a result, by smoothly merging the leakage steam S1 from the sealing devices 15 and 50 into the main flow of the steam S, the mixing loss in the merged portion can be reduced to improve the blade row effect, and the performance of the steam turbine 10 can be improved.

In the rotary machine of the present embodiment, the caulking groove 32 is provided on the upstream side in the steam flow direction a1 from the blade mounting groove 31, and the caulking groove 32 is covered by the downstream end portion in the steam flow direction a1 of the seal rings 41 and 51. Accordingly, the caulking groove 32 can be covered with the seal rings 41 and 51 more appropriately with a simple configuration.

In the rotary machine of the present embodiment, a predetermined gap G1 is provided between the end of each of the seal rings 41 and 51 in the steam flow direction a1 and the stationary blade 13. Therefore, even if the casing, the fixed vane 13, and the seal rings 41 and 51 thermally expand, the predetermined gap G1 can suppress the interference of the seal rings 41 and 51 with other members, and can suppress the deformation of the seal rings 41 and 51.

In the rotary machine of the present embodiment, the seal rings 41 and 51 are provided with flat surfaces 43 and 53 along the axial direction a of the rotor 12. Accordingly, the leakage steam S1 leaking from the sealing devices 15 and 50 is caused to flow smoothly through the flat surfaces 43 and 53, and the leakage steam S1 can be smoothly merged into the main stream of the steam S.

In the rotary machine of the present embodiment, the flat surface 43 of the seal ring 41 is continuous with the inner circumferential surface 11a of the housing 11 without any step. Accordingly, the steam S entering the sealing device 15 or the leakage steam S1 leaking from the sealing device 15 is caused to flow smoothly through the flat surface 43 and the inner peripheral surface 11a, whereby the leakage steam S1 can be smoothly merged into the main flow of the steam S.

In the above embodiment, the sealing device is a labyrinth seal, but may be another non-contact seal.

In the above embodiment, the rotary machine according to the present invention is applied to the steam turbine 10, but the present invention is not limited to the steam turbine, and can be applied to a rotary machine such as a compressor or an exhaust turbine in which the internal pressure is higher than the external pressure during operation.

Description of the symbols

10-a steam turbine (rotary machine), 11-a casing, 11 a-an inner peripheral surface, 12-a rotor, 13-a stationary blade, 13 a-a blade root, 13 b-a stationary blade body, 13 c-a retaining step, 14-a rotor blade, 14 a-a rotor blade body, 14 b-a shroud, 14 c-a fin, 14 d-a protrusion, 14 e-a downstream end, 15, 50-a sealing device, 20-a bearing, 21-a turntable, 22-a steam supply port, 23-a steam passage, 24-a blade row portion, 25-an exhaust chamber, 26-a steam discharge port, 27-a sealing member, 31-a blade mounting groove (mounting recess), 32-a caulking groove (caulking recess), 32 a-a 1 st groove, 32 b-a 2 nd groove, 32 c-locking groove, 33-caulking member, 33 a-insertion portion, 33 b-locking portion, 41, 51-seal ring (seal member), 41a, 51 a-mounting portion, 41b, 51 b-coupling portion, 41c, 51 c-seal portion, 41D, 51D-fin, 41D-1-most upstream fin, 41D-2-most downstream fin, 41 f-protrusion, 42-seal member mounting groove, 42a, 52 a-1 st groove, 42b, 52 b-2 nd groove, 42 c-notch portion, 43, 44, 53, 54-flat surface, A-axial direction, A1-steam flow direction, R-radial direction, G1, G2-prescribed gap, S-steam (fluid), S1-leakage steam, D1-1 st distance, d2-distance 2, D3-distance 3.