JP2007032282A - Seal ring for turbine rotor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a seal ring capable of being easily detached from and attached on a turbine rotor and reducing cost by improving workability, and its mounting method. <P>SOLUTION: The seal ring 6 is formed in a C-shape in which both end parts in a circumference direction face via a slit 60, and is provided with an inner diameter side locked part 61 locked to an inner diameter side locking part 13 of a rotor disk 1 from a radial direction inside, and an outer diameter side locked part 62 locked to an outer diameter side locking part 24 of a moving blade segment 2S from a radial direction outside. Also, the seal ring 6 is provided with a first hooking part 63 and a second hooking part 64 on which attaching and detaching tools 8A, 8B are hooked, the first hooking part 63 is positioned separately in radial direction outside of the second hooking part 64. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a seal ring that can be easily attached to and detached from a turbine rotor.

Conventionally, a seal ring is attached to a side portion of the turbine rotor where the rotor blade segment is mounted. This seal ring prevents the rotor blade segment from falling off the rotor disk and prevents leakage from the gas passage through which combustion gas flows. In this way, the efficiency is improved by preventing the leakage of cooling air, and the thermal degradation of the rotor blade segment is prevented (Patent Document 1).
JP-A-11-141305

  As such a seal ring, as shown in the front view of FIG. 10, the C seal ring R whose both ends in the circumferential direction are opposed to each other through the slit S is used on the inner peripheral surface side of the seal ring R. Two protrusions P, P are provided on both sides near the slit S, and a locking hole H for locking the attaching / detaching jig to the protrusion P is formed. Then, the attachment / detachment jig is engaged with the engagement hole H, and the seal ring R is assembled to the side of the mounting portion of the moving blade segment while the diameter of the entire seal ring R is increased or decreased.

  However, in the above seal ring R, since it is necessary to provide two protrusions P having a locking hole H on a part of the inner periphery thereof, the workability is low and the cost is high. A large force is required to assemble to the mounting portion of the moving blade segment while expanding or reducing the diameter of the entire seal ring R by engaging with the engaging hole H, and in addition, a detachable jig is attached to the engaging hole. When the diameter is increased or reduced by being engaged with H, a large force is applied to the portion of the engagement hole H, so that the protrusion P is likely to be deformed. Further, the combustion gas is entrained by the pumping effect of the protrusion P during rotation, and the inside of the cavity between the moving blade and the blade is agitated by the rotation of the protrusion P to increase the temperature in the cavity.

  Therefore, the present invention can improve the workability and reduce the cost, and can improve the efficiency without increasing the temperature in the cavity as in the prior art. It is an object of the present invention to provide a seal ring that can be easily attached to and detached from the portion, and a method for attaching the seal ring.

  In order to achieve the above object, the present invention provides a seal ring that is attached to a turbine rotor having a plurality of blade segments mounted circumferentially on the outer periphery of a rotor disk and seals the mounting portion of the blade segments. , Both ends in the circumferential direction are opposed to each other through the slit, and are provided on the inner side near the rotor disk in the inner periphery, and are locked from the radially inner side to the inner diameter side locking portion of the rotor disk. An inner-diameter-side locked portion, an outer-diameter-side locked portion that is provided on the outer peripheral side and locked to the outer-diameter-side locking portion of the rotor blade segment from the inside in the radial direction, and a detachable jig from the outside. First and second hook portions on which the tool is hooked are provided, and the first hook portion is located farther outward in the radial direction than the second hook portion.

  When attaching the seal ring to the mounting portion of the rotor blade segment, firstly, the attaching and detaching jigs are respectively hooked on the first and second hook portions of the seal ring, and the seal ring is twisted in the direction in which the slit becomes smaller. Thus, the inner diameter side and outer diameter side engaged portions are respectively engaged with the inner diameter side engaging portion and the outer diameter side engaging portion of the rotor disk. Accordingly, the seal ring can be easily attached to the mounting portion of the rotor blade segment with a small force, and can be easily removed from the mounting portion of the seal ring in the same manner. Further, unlike the conventional case, the seal ring does not need to be provided with a protrusion having a locking hole in a part of the inner periphery, and only the first and second hooks are formed on the seal ring. In other words, since machining can be performed only with a cutting machine, the workability is improved and the cost can be reduced. Moreover, unlike the prior art, no protrusion is provided on the seal ring, so that no combustion gas is involved due to the pump effect of this protrusion, and between the moving blade and the blade during rotation of the protrusion. The inside of the cavity is not stirred to raise the temperature in the cavity, and cooling can be performed with a small amount of cooling air, so that the performance can be improved. Further, unlike the prior art, the attaching / detaching jig is not locked in the locking hole, so that the attaching / detaching jig is not deformed.

  In a preferred embodiment of the present invention, the first hook portion is annular. According to this configuration, the resistance during rotation of the seal ring is reduced, and the stirring action in the cavity by the seal ring is reduced.

  In a preferred embodiment of the present invention, the moving blade segment includes a moving blade portion positioned in a combustion gas passage, and an engaging portion that engages with an engagement recess of the rotor disk. A positioning member is provided that protrudes into a space formed by the outer peripheral surface of the rotor disk and the rotor blade segment and matches the circumferential position of the slit with the engaging portion of the rotor blade segment. According to this configuration, since the circumferential position of the slit matches the engaging portion of the rotor blade segment by the positioning member, combustion gas passing through the gas passage is prevented from leaking through the slit. Further, when the turbine rotor is cooled with cooling air, the cooling air is prevented from blowing through the slit.

  Furthermore, in a preferred embodiment of the present invention, the opening direction of the slit to the ring outer surface forms an obtuse angle with the rotation direction. According to this configuration, the resistance caused by the slit during rotation of the seal ring is reduced, and the stirring action in the cavity by the seal ring is reduced.

  The method of attaching the seal ring to the rotor disk according to the present invention uses two attachment / detachment jigs having first and second hanging claws, and the first and second hanging claws are arranged in the circumferential direction of the seal ring. On both sides of the slit in the first and second hooks, respectively, and the seal ring is reduced in diameter by twisting in a direction in which the slit becomes smaller, so that the inner diameter side and the outer diameter side are locked. The portion is locked to the inner diameter side locking portion and the outer diameter side locking portion of the rotor disk.

  According to this method, the seal ring can be reduced in diameter by twisting the vicinity of the slit of the seal ring with two mounting jigs, so that the seal ring can be easily attached to and detached from the rotor disk with a small force. be able to.

  According to the present invention, the attachment / detachment of the seal ring with respect to the mounting portion of the rotor blade segment can be easily performed with a small force. Further, since the seal ring can be processed only by cutting, the workability is improved and the cost can be reduced. Moreover, it is possible to avoid a rise in the temperature in the cavity due to the conventional entrainment of combustion gas and stirring in the cavity during rotation.

  The turbine rotor of the present invention is used for a gas turbine, for example. The gas turbine includes a compressor that compresses air, a combustor that supplies and burns fuel to the compressed air from the compressor, and a turbine that is driven by high-temperature and high-pressure combustion gas from the combustor. Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view showing a main part of a turbine provided with a turbine rotor according to an embodiment of the present invention. This turbine rotor T has a rotor blade 1 mounted on the outer periphery of a rotor disk 1, and a first stage turbine rotor T, a second stage stator blade 3, and a second stage turbine rotor T are arranged downstream of the first stage stator blade 3. They are arranged sequentially. High-temperature and high-pressure combustion gas G from the combustion chamber of the gas turbine is supplied to the combustion gas passage 4 in which the rotor blades 2 and the blades 3 are arranged, and the turbine rotor T is rotated by the combustion gas G to obtain power. The rotor blade 2 is covered at its radially outer side by a shroud 5 supported by a housing.

  As shown in the front view of FIG. 2, the moving blade 2 has a plurality of moving blade segments 2 </ b> S arranged in the circumferential direction of the rotor disk 1. The moving blade segment 2S includes a moving blade portion 21 disposed in the passage 4 for the combustion gas G, and an engaging portion 23 provided integrally with a base portion 22 on the base side thereof. The engaging portion 23 is a dovetail type having a bulging portion 23a that bulges on both sides in the circumferential direction. On the other hand, an engagement recess 11 that is recessed from the outer peripheral surface 10 and receives the engagement portion 23 is formed in the outer peripheral portion of the rotor disk 1 so as to penetrate in the axial direction. The moving blade segment 2S is attached to the outer periphery of the rotor disk 1 at regular intervals in the circumferential direction by sliding the engaging portion 23 into the recess 11 in the axial direction. As shown in FIG. 1, the rotor disk 1 is formed with an air passage 12 leading to the engagement recess 11, and the cooling air extracted from the compressor is blown out from the air passage 12 to the engagement recess 11. The rotor blade segment 2S is cooled.

  FIG. 3 is an enlarged longitudinal sectional view showing a portion where the seal ring is attached to the rotor disk 1. As shown in the figure, the axially opposite outer portions of the engagement recess 11 of the rotor disk 1 prevent the moving blade segment 2S from falling off the engagement recess 11 and the combustion gas passage 4 In order to prevent leakage of the combustion gas G passing through the engagement recess 11 or the like, a seal ring 6 is attached.

  The seal ring 6 is attached to the rotor disk 1 as follows. An annular inner diameter side locking portion 13 is formed on the outer peripheral portion of the rotor disk 1 on the outer side in the axial direction so as to protrude in the axial direction, and the pedestal portion 22 of the rotor blade segment 2S is provided. On the inner surface side of the axially outer position, a groove-shaped outer diameter side locking portion 24 that opens radially inward is formed. The outer diameter side locking portion 24 forms an annular groove facing inward in the radial direction when the rotor blade segments 2S are arranged in the circumferential direction of the rotor disk 1. On the other hand, the seal ring 6 has an annular recess that is locked from the radially inner side to the inner diameter side locking portion 13 of the rotor disk 1 at the inner surface position near the rotor disk 1 on the inner peripheral surface side. The inner diameter side locked portion 61 is formed. Further, on the outer peripheral side of the seal ring 6, an outer diameter side locked portion 62 that is locked to the outer diameter side locking portion 24 from the radially inner side is formed. This outer diameter side locked portion 62 forms the outer peripheral end of the seal ring 6. The inner diameter side locked portion 61 and the outer diameter side locked portion 62 of the seal ring 6 are locked to the inner diameter side locking portion 13 and the outer diameter side locking portion 24 of the rotor disk 1 from the radially inner side. Thus, the seal ring 6 is attached to both sides in the axial direction (front-rear direction) of the engagement recess 11 of the rotor disk 1. The seal ring 6 may be attached only to one side of the engagement recess 11 in the axial direction.

  Further, a sharp and annular first hook portion 63 projecting obliquely outward in the radial direction is provided on the outer peripheral side of the seal ring 6 at the inner peripheral side position, and the inner peripheral surface side of the seal ring 6 is also provided. The second hooking portion 64 is formed so as to protrude radially inward, and the first hooking portion 63 is separated from the second hooking portion 64 radially outward. Are arranged. The second hook 64 is formed by the inner peripheral surface of the seal ring 6.

  4 is a front view of a part of the seal ring 6, and FIG. 5 is a side view thereof. As shown in FIG. 4, the seal ring 6 is formed in a C shape in which both ends in the circumferential direction face each other through the slit 60, and the opening direction of the slit 60 to the outer surface of the ring is an obtuse angle with respect to the rotation direction. It is said that. That is, as shown in FIG. 5, when the rotation direction of the seal ring 6 is X and the opening direction of the slit 60 to the outer surface of the ring is Y, the angle θ formed by X and Y exceeds 90 °, that is, The opening direction Y is set to face backward with respect to the rotation direction X. In this way, the air resistance by the slit 60 becomes small when the seal ring 6 rotates in the X direction. Further, the stirring action by the seal ring 6 in the cavity S1 (see FIG. 1) formed between the moving blade and the blades 2 and 3 is reduced.

  As shown in FIG. 2, the seal ring 6 is positioned and attached so that the circumferential position of the slit 60 matches the position of the engaging portion 23 of the rotor blade segment 2S. When positioning the seal ring 6, as shown in FIG. 6, a rivet 7 that is a positioning member is used, and two of the rivets 7 are separated from each other at a predetermined interval with the slit 60 of the seal ring 6 interposed therebetween. Each rivet 7 is placed in a space S2 formed between the outer peripheral surface 10 of the rotor disk 1 and a side portion protruding outward from the engagement recess 11 of the engagement portion 23 provided in the rotor blade segment 2S. The rivet 7 is caulked and fixed by a fixing tool such as a punch, and is brought into contact with the circumferential side portion of the engaging portion 23. In this way, the movement of the seal ring 6 is regulated by each rivet 7, and the slit 60 of the seal ring 6 is attached so as to match the engaging portion 23 of the rotor blade segment 2S.

  FIG. 7 is a perspective view showing a pair of left and right attachment / detachment jigs 8A and 8B used for attaching / detaching the seal ring 6 to / from the rotor disk 1. FIG. These attaching / detaching jigs 8A and 8B are provided at the grip part 81 to be gripped during operation and the tip of the grip part 81, and are attached to the first and second hook parts 63 and 64 of the seal ring 6 in FIG. First and second hooking claws 82 and 83 to be hooked are provided. In the illustrated embodiment, a mounting portion 81 a is provided at the tip of the grip portion 81, and a claw member 84 in which the hooking claws 82 and 83 are formed is fixed to the mounting portion 81 a by a plurality of fasteners 85. Yes. The claw member 84 is formed with a groove having a V-shaped cross section that is hooked on the first hook portion 63 (FIG. 6) on one side in the width direction on the base end side, and this groove portion is the first portion. A protrusion having a substantially L-shaped cross section is integrally formed on the tip side of the claw member 84 on the side opposite to the groove forming side, and this protrusion is formed on the second hooking claw 83. Has been. Both the hooking claws 82 and 83 are displaced along the longitudinal direction P of the grip portion 18 of each of the attachment / detachment jigs 8A and 8B. The attaching / detaching jigs 8A and 8B are provided with first and second hanging claws 82 and 83 symmetrically, respectively.

  FIG. 8 is a partially omitted front view for explaining a method of attaching the seal ring 6 to the rotor disk 1, and FIG. 9 is a longitudinal sectional view of an essential part thereof. As shown in FIG. 9, when the seal ring 6 is attached to both axially outer sides of the engagement recess 11 of the rotor disk 1, first, the attachment / detachment jigs 8A and 8B are attached to the seal ring as shown in FIG. The first hooking claws 82 of the attachment / detachment jigs 8A and 8B shown in FIG. 9 are placed on the first hooking portion 63 of the seal ring 6 and the The second hook 83 is hooked on the second hook 64 of the seal ring 6. Subsequently, the grip ring 81 of each of the attachment / detachment jigs 8A and 8B shown in FIG. 8 is gripped and a force is applied in the ZZ line direction so that the slit 60 of the seal ring 6 is reduced. Twist 6 to reduce diameter. In this state, the inner and outer diameter engaged portions 61 and 62 of the seal ring 6 shown in FIG. 9 are connected to the inner and outer diameter engaging portions 13 and 24 provided on the rotor disk 1 and the rotor blade segment 2S. Each is locked from the radially inner side. Thereafter, the twisting force of the seal ring 6 by the attaching / detaching jigs 8A and 8B is released, and the seal ring 6 is supported between the inner diameter and outer diameter side locking portions 13 and 24 by a restoring force. Further, the seal ring 6 is removed from the rotor disk 1 in the same manner as described above.

  With the above configuration, the seal ring 6 can be easily attached to and detached from the rotor disk 1 with a small force. That is, when the seal ring 6 is attached and detached, the first and second hooking claws 82 and 83 provided on the attaching / detaching jigs 8A and 8B in FIG. 8 are formed on the seal ring 6 in FIG. Since the torsional force is applied to the seal ring 6 in the direction of diameter reduction by being engaged with the hooking parts 63 and 64, a detachable jig is inserted into the engagement hole H as shown in FIG. The seal ring 6 can be easily reduced in diameter and attached / detached with a small force without requiring a large force as in the case of reducing the diameter 6. Further, since it is only necessary to form the first and second hook portions 63 and 64 of FIG. 9 on the seal ring 6 by cutting, the workability is improved and the cost can be reduced. Furthermore, since the first hook 63 of the seal ring 6 is annular and the second hook 64 is formed by the inner peripheral surface of the seal ring 6, an increase in resistance during rotation is suppressed. The Moreover, the seal ring 6 does not entrain the combustion gas G passing through the passage 4 in FIG. 1 or stir the cavity S1 between the moving blade and the blades 2 and 3 to increase the temperature in the cavity. Cooling is possible with less cooling air.

  Further, as shown in FIG. 2, the seal ring 6 is attached using a positioning member (rivet) 7 so that the slit 60 matches the position of the engaging portion 23 of the blade segment 2S. The combustion gas G passing through the passage 4 is prevented from leaking from the slit 60 into the space S2, and cooling air entering the space S2 from the air passage 12 provided in the rotor disk 1 of FIG. Blowing out to the cavity S1 side is also prevented. At this time, as shown by the phantom line in FIG. 1, the first hooking portion 63 provided on the seal ring 6 is provided on the side surface of the support ring 30 that supports the blade 3 that faces the seal ring 6 in the radial direction. A sealing wall 31 protruding in the axial direction is formed so as to face the radial direction with a predetermined gap, and the combustion gas passage 4 of the cooling air is formed by the labyrinth effect by the sealing wall 31 when the blade segment 2S rotates. It is also possible to prevent leaks.

It is a longitudinal cross-sectional view which shows the principal part of the turbine rotor concerning one Embodiment of this invention. FIG. 4 is a partially broken front view showing a portion where a rotor blade segment is attached to a rotor disk. It is a longitudinal cross-sectional view which expands and shows the attachment part to the rotor disk of a seal ring. It is a front view which shows a part of seal ring. It is the same side view. It is sectional drawing along the VI-VI line of FIG. It is a perspective view of the jig | tool for attachment / detachment used in order to attach or detach a seal ring to a rotor disk. It is the front view which abbreviate | omitted partially explaining the attachment method to the rotor disk of a seal ring. It is a longitudinal cross-sectional view of the principal part. It is a front view which shows a part of conventional seal ring.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotor disk 10 Outer peripheral surface 11 Engagement recess 13 Inner diameter side latching part 2 Rotor blade 2S Rotor blade segment 21 Rotor blade part 23 Engagement part 24 Outer diameter side latching part 4 Combustion gas passage 6 Seal ring 60 Slit 61 Inner diameter Side locked portion 62 Outer diameter side locked portion 63 First hook portion 64 Second hook portion 8A, 8B Detachment jig T Turbine rotor X Rotating direction Y Opening direction

Claims (5)

A seal ring which is concentrically attached to a turbine rotor having a plurality of blade segments mounted circumferentially on the outer periphery of the rotor disk and seals the mounting portion of the blade segments;
Formed in a C-shape with both ends in the circumferential direction facing each other through a slit,
An inner diameter side locked portion that is provided on the inner surface side near the rotor disk in the inner peripheral portion and is locked from the radially inner side to the inner diameter side locking portion of the rotor disk, and a rotor blade segment that is provided on the outer peripheral side An outer diameter side locked portion locked from the radially inner side to the outer diameter side locking portion, and first and second hook portions on which an attaching / detaching jig is hooked from the outer side,
A seal ring for a turbine rotor, wherein the first hooking portion is located radially outward from the second hooking portion.   2. The seal ring of the turbine rotor according to claim 1, wherein the first hook portion is annular.   3. The blade segment according to claim 1, wherein the blade segment includes a blade portion positioned in a combustion gas passage, and an engagement portion that engages with an engagement recess of the rotor disk. A turbine rotor seal ring provided with a positioning member that projects into a space formed by an outer peripheral surface and a blade segment and matches a circumferential position of the slit with an engaging portion of the blade segment.   The seal ring of the turbine rotor according to claim 1, 2, or 3, wherein an opening direction of the slit to an outer surface of the ring forms an obtuse angle with a rotation direction.   A method of attaching the seal ring according to any one of claims 1 to 4 to a rotor disk, wherein two attachment / detachment jigs having first and second hanging claws are used, and the first and second The hooking claw is respectively hooked on the first and second hooks on both sides of the slit in the circumferential direction of the seal ring, and the diameter of the seal ring is reduced by twisting in the direction in which the slit becomes smaller. And a method of attaching a seal ring for locking the locked portion on the outer diameter side to the inner diameter side locking portion and the outer diameter side locking portion of the rotor disk.

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