JP2015200301A - Gas turbine including seal structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas turbine which has a seal structure capable of maintaining a sealing property of the seal structure and capable of improving service life of a member of the seal structure by reducing stress concentration around a disc engaging part.SOLUTION: A gas turbine includes: a projection part which is arranged between a plurality of rotor discs arrayed in a rotor axial direction, which extends in the rotor axial direction so as to oppose with each other from an adjacent rotor disc and in which an annular groove part is formed on an opposing end surface; an annular seal plate which is arranged in a rotor circumferential direction in the groove part, and in which a seal plate engaging part is formed on a side edge; and a rotation stop member which is locked to the projection part via a disc engaging part formed at the projection part, and which locks the seal plate via the seal plate engaging part. The projection part is an annular projecting part in which tips in the rotor axial direction are sandwiching the groove part, and a stress relaxation part which is adjacent to the disc engaging part in the rotor circumferential direction is provided at the projecting part. The stress relaxation part is arranged so as to overlap the seal plate in a rotor radial direction.

Description

  The present invention relates to a gas turbine having a seal structure that prevents leakage of combustion gas or a cooling medium between rotor disks of the gas turbine.

  The rotor of the turbine is composed of a plurality of rotor disks around the rotor shaft. An annular projecting portion is provided on opposing surfaces of adjacent rotor disks so as to face each other around the rotor shaft, and a groove portion is provided on the opposing surface at the tip of the projecting portion along the circumferential direction of the rotor. An annular seal plate is disposed along the rotor circumferential direction of the groove. The seal plate is pressed outward in the rotor radial direction of the groove portion by centrifugal force due to the rotation of the rotor disk, and the radially outer surface of the groove portion and the radial outer surface of the seal plate are in close contact with each other, and the cooling medium introduced into the rotor Is sealed. In such a seal structure, since the seal plate is not fixed to the rotor disk, there is a possibility that relative movement within the groove portion occurs in the rotor circumferential direction and the rotor axial direction.

  As a known example of a seal structure that suppresses the relative movement of the seal plate within the groove, a seal structure provided with a seal plate anti-rotation member is known (for example, Patent Document 1).

  In the rotor of a turbine, the rotor disk has a disk ring-shaped flange extending in a direction perpendicular to the rotor axis at the end portion of the cylindrical curved plate, and the adjacent rotor disk is located on the inner circumferential edge of the flange. It is connected with a bolt through a notch provided along. The centrifugal force generated in the rotor disk by the rotation generates a circumferential stress in the flange coupling portion. Therefore, stress concentration occurs in the notch in the flange, which may reduce the service life of the member.

  As a known example of a rotor for reducing this stress concentration, a rotor having a hole or another notch between notches in a flange is known (for example, Patent Document 2).

Japanese Patent No. 4822716 JP-T-2002-519564

  By the way, in a gas turbine having a seal structure provided with a seal plate anti-rotation member, the radial outer surface of the seal plate is changed to the radial outer surface of the groove portion by centrifugal force due to the rotation of the rotor disk in order to maintain the sealing performance. It is necessary to adhere. On the other hand, in order to suppress the relative movement of the seal plate in the circumferential direction in the groove, a hole or a notch for inserting the detent member is provided as a disk engaging portion in the projecting portion. Circumferential stress is also generated in the overhanging portion by the centrifugal force generated by the rotation of the rotor disk. For this reason, stress concentration may occur around the disk engaging portion provided in the overhanging portion. When stress is concentrated on a part, the position where the stress is concentrated may be less durable than the other part. If there is such a portion with low durability, the life of the apparatus may be shortened.

  The present invention has been made in view of the above, and maintains the sealing performance of the seal structure and improves the operational life of the member of the seal structure by reducing the stress concentration around the disk engaging portion. An object of the present invention is to provide a gas turbine having a seal structure capable of achieving the above.

  In order to solve the above problems, a gas turbine having a seal structure according to an aspect of the present invention is disposed between a plurality of rotor disks arranged in the rotor axial direction so as to face each other from the adjacent rotor disks. Extending in the axial direction of the rotor, and an overhanging portion having an annular groove formed on the opposing end surface, and an annular portion disposed in the circumferential direction of the rotor in the groove and having a seal plate engaging portion formed on the side edge A seal plate, and a detent member that is locked to the overhanging portion via a disk engaging portion formed in the overhanging portion and that locks the seal plate through the seal plate engaging portion. The projecting portion is an annular projecting portion with a tip in the rotor axial direction sandwiching the groove portion, and the projecting portion is adjacent to the disk engaging portion in the rotor circumferential direction to relieve stress. And the stress relieving part is provided with the seal. Characterized in that it is arranged so as to overlap the rotor radial direction relative.

  According to such a configuration, it is possible to improve the operational life of the member having the seal structure by reducing the stress concentration around the disk engaging portion while maintaining the sealing performance of the seal structure.

  Further, in the gas turbine provided with the seal structure according to another aspect of the present invention, the protruding portion includes a radially outer protruding portion that is radially outer than the seal plate and a radially inner diameter than the seal plate. And the stress relaxation portion is formed on at least one of the radially outer projecting portion and the radially inner projecting portion.

  According to such a configuration, it is possible to improve the operational life of the member having the seal structure by reducing the stress concentration around the disk engaging portion while maintaining the sealing performance of the seal structure. In particular, stress concentration at a location where stress concentration occurs, for example, in the vicinity of the corner of the disk engaging portion can be reduced. Here, the corner portion of the disk engaging portion is an end portion of the disk engaging portion in the rotor axial direction.

  Moreover, the gas turbine provided with the seal structure according to another aspect of the present invention is characterized in that the stress relaxation portion penetrates the radial outer protrusion and the radial inner protrusion in the rotor radial direction. .

  According to such a configuration, it is possible to improve the operational life of the member having the seal structure by reducing the stress concentration around the disk engaging portion while maintaining the sealing performance of the seal structure. Further, by forming the stress relaxation portion as a pair of through holes, the stress relaxation portion can be easily processed.

  Further, in the gas turbine provided with the seal structure according to another aspect of the present invention, the stress relieving portion may be configured such that either the radially outer protruding portion or the radially inner protruding portion of the protruding portions has a rotor diameter. It penetrates in the direction.

  According to such a configuration, it is possible to improve the operational life of the member having the seal structure by reducing the stress concentration around the disk engaging portion while maintaining the sealing performance of the seal structure. In particular, stress concentration at a location where stress concentration occurs, for example, in the vicinity of the corner of the disk engaging portion can be reduced. Moreover, the stress relaxation part can be easily processed by using the stress relaxation part as a through hole.

  Moreover, the gas turbine provided with the seal structure according to another aspect of the present invention is characterized in that the stress relaxation portion is formed only in a radially outer protruding portion of the protruding portions.

  According to such a configuration, it is possible to improve the operational life of the member having the seal structure by reducing the stress concentration around the disk engaging portion while maintaining the sealing performance of the seal structure. In particular, the stress concentration in the vicinity of the corner portion of the disk engaging portion located at the radially outward projecting portion where the stress concentration occurs can be reduced.

  Further, in the gas turbine provided with the seal structure according to another aspect of the present invention, the stress relaxation portion is formed on a front side and a rear side in a rotor circumferential direction with respect to the disk engagement portion. To do.

  According to such a configuration, it is possible to improve the operational life of the member having the seal structure by reducing the stress concentration around the disk engaging portion while maintaining the sealing performance of the seal structure. In particular, it is possible to reduce stress concentration generated in the vicinity of the disk engaging portion on both sides in the circumferential direction of the rotor with respect to the disk engaging portion.

  In the gas turbine provided with the seal structure according to another aspect of the present invention, the stress relaxation portion is an oblong hole that is long in the circumferential direction of the rotor.

  According to such a configuration, it is possible to improve the operational life of the member having the seal structure by further reducing the stress concentration around the disk engaging portion while maintaining the sealing performance of the seal structure.

  Further, in the gas turbine provided with the seal structure according to another aspect of the present invention, a plurality of the stress relaxation portions are respectively formed on the front side and the rear side in the rotor circumferential direction with respect to the disk engaging portion. Features.

  According to such a configuration, it is possible to improve the operational life of the member of the seal structure by further reducing the stress concentration around the disk engaging portion while maintaining the sealing performance of the seal structure.

  Moreover, in the gas turbine provided with the seal structure according to another aspect of the present invention, the stress relaxation portion is a hole, and the inner walls at both ends in the axial direction that form the maximum axial width of the hole are opposed to each other. The inner wall on the side farther from the end surface in the axial direction of the rotor forms the maximum axial width of the disk-engaging portion of the hole-shaped disk engaging portion, and is disposed in the inner wall near the end surface and in the groove portion. It is arrange | positioned between the said side edges of a board, It is characterized by the above-mentioned.

  According to such a configuration, when the stress relaxation part is a hole, the service life of the member of the seal structure is improved by reducing the stress concentration around the disk engagement part while maintaining the sealing performance of the seal structure. Can be made. In particular, the stress in the vicinity of the inner wall near the end surface facing the rotor axial direction of the protruding portion in the vicinity of the inner walls at both ends in the axial direction forming the maximum axial width of the disk-shaped disk engaging portion where stress concentration occurs. Concentration can be reduced.

  In the gas turbine having the seal structure according to another aspect of the present invention, the stress relaxation portion is a notch formed in the rotor axial direction from the end surface of the overhang portion, and the shaft of the notch The inner wall farthest from the end face that forms the deepest part in the direction is disposed in the groove part and the inner wall near the end face among the inner walls at both ends in the axial direction that form the maximum axial width of the disk-shaped disk engaging part. It is arranged between the side edges of the seal plate.

  According to such a configuration, when the stress relaxation portion is a notch formed in the axial direction of the rotor from the end surface of the overhang portion, the stress concentration around the disk engaging portion is maintained while maintaining the sealing performance of the seal structure. The service life of a member having a seal structure can be improved. In particular, it is possible to reduce stress concentration in the vicinity of the inner wall near the axial end face of the overhanging portion of the inner walls at both ends in the axial direction forming the maximum axial width of the hole-shaped disk engaging portion where stress concentration occurs. it can.

  According to the gas turbine having the seal structure of the present invention, it is possible to improve the operational life of the member of the seal structure by reducing the stress concentration around the disk engaging portion while maintaining the seal performance of the seal structure. it can.

FIG. 1 is a conceptual diagram showing a general configuration of a gas turbine. FIG. 2 shows the structure around the rotor disk of the gas turbine. FIG. 3 is a structural diagram around the seal plate. FIG. 4 is an in-groove mounting view of the seal plate according to the first embodiment of the present invention. FIG. 5 is a plan view of the periphery of the detent member according to the first embodiment of the present invention. 6 is a cross-sectional view of the disk engaging portion according to the first embodiment of the present invention, taken along a plane including the rotor axis in a state where the seal plate is incorporated in the groove portion (AA portion in FIG. 5). ). 7 is a cross-sectional view of the stress relaxation portion according to the first embodiment of the present invention, taken along a plane including the rotor axis in a state where the seal plate is incorporated in the groove portion (BB portion in FIG. 5). It is. FIG. 8 is a cross-sectional view of a first modification of the first embodiment of the present invention, taken along a plane including the rotor axis in a state where the seal plate is incorporated in the groove. FIG. 9 is a cross-sectional view of a second modification of the first embodiment of the present invention, taken along a plane including the rotor axis in a state where the seal plate is incorporated in the groove. FIG. 10 is a cross-sectional view of a third modification of the first embodiment of the present invention, taken along a plane including the rotor axis in a state where the seal plate is incorporated in the groove. FIG. 11 is a plan view around the disk engaging portion according to the first embodiment of the present invention. FIG. 12 is a plan view around the disk engaging portion of the fourth modified example of the first embodiment of the present invention. FIG. 13 is a plan view around the disc engaging portion of the fifth modified example of the first embodiment of the present invention. FIG. 14 is a plan view around the disc engaging portion of the sixth modified example of the first embodiment of the present invention. FIG. 15 is an in-groove installation view of the seal plate according to the second embodiment of the present invention. FIG. 16 is a plan view of the periphery of the detent member according to the second embodiment of the present invention. FIG. 17 is a cross-sectional view of the disk engaging portion according to the second embodiment of the present invention, taken along a plane including the rotor axis in a state where the seal plate is incorporated in the groove portion (CC portion in FIG. 16). ).

  A mode for carrying out the present invention (hereinafter referred to as an embodiment) will be described in detail with reference to the drawings.

(First embodiment)
A gas turbine provided with a seal structure according to the first embodiment will be described with reference to FIGS. 1 to 7. FIG. 1 is a conceptual diagram showing a general configuration of a gas turbine. As shown in FIG. 1, the gas turbine compresses air by a compressor 51, introduces compressed air into a combustor 52, inputs fuel to generate combustion gas, and introduces the generated combustion gas into a turbine 53. Thus, the turbine is rotated to take out electric power from the generator 54. In order to improve the efficiency of the gas turbine, it is necessary to generate a higher-temperature combustion gas. Therefore, a cooling medium 57 such as cooling air or cooling steam is used for the purpose of cooling the moving and stationary blade portions of the turbine.

  FIG. 2 shows the structure around the rotor disk of the gas turbine. FIG. 3 is a structural diagram around the seal plate. As shown in FIG. 2, the rotor of the turbine 53 includes a plurality of rotor disks 60 around the rotor shaft 58.

  As shown in FIG. 3, the rotor disk 60 has an annular projecting portion 3 extending in the rotor axial direction so as to surround the rotor shaft 58 and face each other from the opposed surfaces of the adjacent rotor disks 60 in the rotor axial direction. The groove portion 4 is provided along the circumferential direction of the rotor on the end surface 13 which is a surface facing the tip of the overhang portion 3. The rotor of the turbine 53 is provided with an annular seal plate 2 along the circumferential direction of the groove 4. The seal plate 2 is pressed outward in the rotor radial direction of the groove portion 4 by centrifugal force due to the rotation of the rotor disk 60, and the radial outer surface of the groove portion 4 and the radial outer surface of the seal plate 2 are in close contact with each other. By doing so, the cooling medium 57 introduced into the rotor and the combustion gas 56 from the combustor 52 are sealed. As described above, the turbine is provided with the groove portion 4 in the projecting portion 3 of the rotor disk 60 and the seal structure in which the seal plate 2 is inserted into the groove portion 4 facing the rotor disk 60, thereby introducing the cooling medium introduced into the rotor. 57 prevents the gas from flowing into the gas path 55 of the turbine 53 and prevents the combustion gas 56 from the combustor flowing through the gas path 55 from flowing into the rotor.

  Next, the seal structure 1 of the first embodiment will be described in more detail. FIG. 4 is a view in which the seal plate according to the first embodiment of the present invention is attached in the groove. As shown in FIG. 4, the seal structure 1 according to the first embodiment is provided on the rotor disk 60 and has a protruding portion 3 having an annular groove portion 4, a seal plate 2 inserted into the groove portion 4, and And a detent member 8 for restricting circumferential movement in the groove 4 of the seal plate 2.

  The overhanging portion 3 projects from a surface of the adjacent rotor disk 60 facing the rotor axial direction at a position facing the rotor axial direction. The tip of the overhanging portion 3, that is, the tip portion facing the overhanging portion 3 becomes the protruding portion 5. The groove part 4 is provided in the end surface 13 of the protrusion part 5 of the overhang | projection part 3 which opposes cyclically | annularly in a rotor axial direction. The groove 4 extends in the rotor axial direction, and the end opposite to the end surface 13 in the rotor axial direction is the bottom surface 14. The protrusion 5 is divided into a radially outer protrusion 11 positioned on the outer side in the rotor radial direction and a radially inner protrusion 12 positioned on the inner side in the rotor radial direction by forming the groove 4. In other words, in the protruding portion 5, a radially outer portion from the groove portion 4 becomes the radially outer protruding portion 11, and a radially inner portion from the groove portion 4 becomes the radially inner protruding portion 12.

  The seal plate 2 is a member in which at least two annular plates are slightly shifted in the circumferential direction, overlapped in the radial direction, and fixed with a rotation preventing member 8. The seal plate 2 is annularly disposed in the groove portion 4 provided on the end surface 13 of the protruding portion 3 of the adjacent rotor disk 60 facing the rotor axial direction. The seal plate 2 is fixed by a rotation stop member 8 via a seal plate engaging portion 7 provided on the seal plate 2. When the rotor disk 60 rotates, the seal plate 2 moves outward in the radial direction by centrifugal force and comes into close contact with the protruding portion 5. That is, the seal plate 2 is in close contact with the radially inner side surface of the radially outer projecting portion 11 of the projecting portion 5 and the radially outer surface of the seal plate 2 while the turbine 53 is rotating. Thereby, as described above, the turbine 53 is sealed by the contact surface formed between the radially outer surface of the seal plate 2 and the radially inner surface of the radially outer projecting portion 11, and the combustion gas is overhanged. 3 (seal plate 2) is prevented from flowing into the inside (cooling medium passage side). For the same reason, the cooling medium inside the rotor is prevented from flowing out from the seal plate 2 to the gas path side (combustion gas passage side, radially outward from the overhang portion 3).

  In the seal structure 1 of the present embodiment, as shown in FIG. 4, the seal plate 2 is inserted into each groove portion 4 formed in the overhang portion 3 arranged to face the rotor axial direction. Further, the non-rotating member 8 is inserted into the disk engaging portion 6 from the inner side in the rotor radial direction, and the sealing plate 2 is brought into contact with the arc-shaped sealing plate engaging portion 7 provided on the sealing plate 2. Assembled. With such a configuration, the seal plate 2 is in close contact with the radially inner side surface of the radially outer projecting portion 11, and the rotor disk via the seal plate engaging portion 7, the anti-rotation member 8 and the disk engaging portion 6. It is latched with respect to 60 overhang | projection part 3, and the movement of a rotor axial direction and a rotor circumferential direction is restrained in the groove part 4. FIG.

  The disk engaging portion 6 is formed so as to penetrate the groove portion 4 provided in the protruding portion 3 of the rotor disk 60 (the protruding portion 5 of the protruding portion 3) in the rotor radial direction. That is, the disk engaging portion 6 is disposed as a hole penetrating the protruding portion 3 from the outside in the rotor radial direction toward the inside. Further, the disk engaging portions 6 are arranged in the same number and position as the corresponding rotation stop members 8 of the corresponding seal plate 2 in the circumferential direction of the rotor. Moreover, the disk engaging part 6 may be provided in both the overhang | projection parts 3 which oppose a rotor axial direction, and may be provided only in one side.

  As shown in FIGS. 4 and 5, the seal plate engaging portion 7 is provided in an arc shape on the side edge 15 of the seal plate 2. This seal plate engaging portion 7 may be provided on only one of the side edges 15 of the seal plate or on both side edges 15.

  The detent member 8 includes a detent pin 35 and a holding ring 36. The anti-rotation member 8 is inserted into the disc engaging portion 6 and is locked to the overhang portion 3 via the disc engaging portion 6. Further, the seal plate 2 is locked to the overhanging portion 3 via the seal plate engaging portion 7 and the anti-rotation member 8. Note that a plurality of anti-rotation members 8 may be provided in the circumferential direction of the rotor.

  As shown in FIGS. 4 and 5, the stress relaxation portion 9 is provided adjacent to the disk engaging portion 6 in the circumferential direction of the rotor. The stress relaxation portion 9 being adjacent to the disk engaging portion 6 in the rotor circumferential direction is an arrangement in which the center position of the disk engaging portion 6 in the rotor circumferential direction and the center position of the stress relaxing portion 9 in the rotor circumferential direction do not coincide with each other. This means that the center positions of the two are shifted in the circumferential direction of the rotor, and the stress relieving portion 9 and the disk engaging portion 6 are disposed in the vicinity. The stress relaxation portion 9 is disposed so as to overlap the seal plate 2 in the rotor radial direction. With such a configuration, the stress relaxation portion 9 reduces stress concentration caused by the circumferential stress generated around the disk engaging portion 6 of the protruding portion 5. Further, since the stress relaxation portion 9 is disposed so as to overlap the seal plate 2 in the rotor radial direction, the seal plate 2 rotates in close contact with the protruding portion 5 due to the centrifugal force caused by the rotation of the rotor disk 60. When it does, it will be in the state obstructed by the seal plate 2. Thereby, the sealing performance of the seal structure 1 is maintained.

  As shown in FIG. 6, the disk engaging portion 6 is formed as a through hole into which the anti-rotation member 8 can be inserted, for example. The disk engaging portion 6 is bored across the groove portion 4 over the entire length of the overhang portion 3 in the rotor radial direction from the outside in the rotor radial direction toward the inside. The disk engaging portion 6 formed as a through hole is provided at a position where the bottom surface 14 forming the groove 4 is substantially at the center of the through hole. That is, the disk engaging portion 6 is provided in the overhang portion 3 so as to partially penetrate the groove portion 4 and the seal plate 2 in the rotor radial direction.

  Further, as shown in FIG. 6, the disc engagement portion 6 has an inner circumference that faces the inner side of the rotor radial direction so that the inner diameter that faces the outer side in the rotor radial direction is larger than the inner diameter that faces the inner side in the rotor radial direction. A step portion 37 is provided on the outer side of the surface in the rotor axial direction. In the disk engaging portion 6, the inner peripheral surface on the small diameter side located on the inner side in the rotor radial direction with the stepped portion 37 as a boundary is inscribed in the anti-rotation pin 35 constituting the anti-rotation member 8. Further, the disk engaging portion 6 has an inner peripheral surface on the large diameter side of the disk engaging portion 6 located on the outer side in the rotor radial direction with the stepped portion 37 as a boundary inside the holding ring 36 constituting the rotation stop member 8. It touches.

  According to the above-described configuration, since the seal plate 2 is fixed to the rotor disk 60 via the anti-rotation member 8, the relative movement of the seal plate 2 in the groove portion 4 is suppressed. Therefore, relative movement of the seal plate 2 in the rotor axial direction and the rotor circumferential direction is suppressed, and wear and replacement frequency of the seal plate 2 are reduced. Further, in the seal structure 1 of the first embodiment, the anti-rotation member 8 is fitted and held in the disk engaging portion 6 formed in the overhang portion 3, so that the anti-rotation member is attached to the seal plate 2. The centrifugal force of 8 does not act. Therefore, the relative movement of the anti-rotation member 8 can be kept small, and damage to the inner walls of the groove 4 and the disk engaging portion 6 can be suppressed.

  Here, the disk engaging portion 6 is provided on the overhanging portion 3 so as to partially penetrate the groove portion 4 and the seal plate 2 in the radial direction of the rotor. There is a possibility that the stress concentration around the engaging portion 6 becomes large. In contrast, in the seal structure 1 of the first embodiment, the stress concentration portion 9 is provided adjacent to the disk engaging portion 6 in the circumferential direction of the rotor, so that the stress concentration around the disk engaging portion 6 in the protruding portion 5 is achieved. Can be reduced. Further, since the stress relieving portion 9 is disposed so as to overlap the seal plate 2 in the rotor radial direction, the seal plate 2 comes into close contact with the protruding portion 5 due to the centrifugal force caused by the rotation of the rotor disk 60. Therefore, since the stress relaxation part 9 provided in the protrusion part 5 is sealed by the seal plate 2, the sealing performance of the seal structure 1 is maintained. Therefore, the seal structure 1 can reduce stress concentration around the disk engaging portion 6 in the protruding portion 5 while maintaining the sealing performance, and can improve the operational life of the protruding portion 5. As a result, the seal structure 1 improves the operational life of the member, particularly the low cycle life.

  Next, as the stress relaxation section 9 according to the first embodiment of the present invention and its modifications, eight stress relaxation sections 9a and 9b having different shapes in the radial direction of the rotor, shapes in the circumferential direction of the rotor, the number, or arrangement thereof are different. , 9c, 9d, 9e, 9f, 9g, 9h will be described. Hereinafter, when a point not related to the shape, number, or arrangement is described, the stress relaxation unit 9 will be described.

  The shape of the stress relaxation portion 9 in the rotor radial direction will be described with reference to FIG. FIG. 7 is a cross-sectional view of the stress relaxation portion according to the first embodiment of the present invention cut along a plane including the rotor axis in a state where the seal plate is incorporated in the groove portion (BB portion shown in FIG. 5) ). As shown in FIG. 7, the stress relaxation portion 9 a penetrates the radially outer protruding portion 11 and the radially inner protruding portion 12 in the rotor radial direction. The stress relaxation part 9a is formed as a pair of through-holes that penetrates the radially outer projecting part 11 and the radially inner projecting part 12 in the rotor radial direction. With such a configuration, the stress relaxation portion 9a can reduce stress concentration around the disk engaging portion 6. Moreover, the stress relaxation part 9a can be easily processed by using the stress relaxation part 9a as a pair of through holes. In addition, the position of the stress relaxation part 9a formed in the radial direction outer side protrusion part 11 and the radial direction inner side protrusion part 12 does not necessarily need to correspond with a rotor axial direction and a rotor circumferential direction.

(First modification)
FIG. 8 is a first modification of the first embodiment of the present invention, and is a cross-sectional view taken along a plane including the rotor axis in a state where the seal plate is incorporated in the groove. 8 is formed on at least one of the radially outer projecting portion 11 and the radially inner projecting portion 12 in the projecting portion 5. The stress relieving portion 9b overlaps only the corner portion of the disk engaging portion 6 located in the radially outer protruding portion 11 among the corner portions of the disk engaging portion 6 in the rotor circumferential direction, and does not penetrate in the rotor radial direction. It is formed as a hole. With such a configuration, the stress relaxation portion 9b can reduce stress concentration particularly in a location where stress concentration occurs, for example, in the vicinity of the corner of the disk engaging portion 6. Here, the corner portion of the disk engaging portion is an end portion of the disk engaging portion in the rotor axial direction. In addition, the stress relaxation portion 9b overlaps with the corner portion of the disk engaging portion 6 in the rotor axial direction when viewed from the circumferential direction of the rotor. It is. In other words, when the stress relaxation portion 9b is moved in the rotor circumferential direction, it is in a state where it overlaps with the position where the corner portion of the disk engaging portion 6 is formed.

(Second modification)
FIG. 9 is a second modification of the first embodiment of the present invention, and is a cross-sectional view taken along a plane including the rotor axis in a state where the seal plate is incorporated in the groove. 9 may penetrate either one of the radially outer projecting portion 11 and the radially inner projecting portion 12 in the projecting portion 5 in the rotor radial direction. The stress relaxation portion 9c overlaps only the corner portion of the disk engaging portion 6 located at the radially inner protruding portion 12 among the corner portions of the disk engaging portion 6 in the rotor circumferential direction and penetrates in the rotor radial direction. It is formed as a hole. With such a configuration, the stress relaxation portion 9c can reduce stress concentration particularly at a location where stress concentration occurs, for example, in the vicinity of the corner of the disk engaging portion 6. Moreover, the stress relaxation part 9c can be easily processed by using the stress relaxation part 9c as a through hole.

(Third Modification)
FIG. 10 is a third modification of the first embodiment of the present invention, and is a cross-sectional view taken along a plane including the rotor axis in a state where the seal plate is incorporated in the groove. The stress relaxation portion 9 d shown in FIG. 10 is formed only on the radially outer protruding portion 11 in the protruding portion 5. The stress relaxation portion 9d overlaps only the corner portion of the disk engaging portion 6 located in the radially outer protruding portion 11 among the corner portions of the disk engaging portion 6 in the rotor circumferential direction and penetrates in the rotor radial direction. It is formed as a hole. Generally, the centrifugal force generated by the rotation of the rotor disk 60 is larger on the outer side in the rotor radial direction than on the inner side in the rotor radial direction. Therefore, the circumferential stress in the protrusion 5 caused by the centrifugal force is larger in the radially outer protrusion 11 than in the radially inner protrusion 12. Therefore, with such a configuration, the stress relaxation portion 9d can reduce the stress concentration in the vicinity of the corner portion of the disk engaging portion 6 located in the radially outer protruding portion 11 where the stress concentration occurs. Moreover, the stress relaxation part 9d can be easily processed by forming the stress relaxation part 9d as a through hole.

  Next, the shape, number, or arrangement of the stress relaxation portion 9 in the rotor circumferential direction will be described with reference to FIGS. 11 to 14. 11 to 14, in order to maintain the sealing performance of the seal structure 1, each of the stress relaxation portions 9 is in relation to the disc engagement portion 6 so as to overlap the seal plate engagement portion 7 in the rotor radial direction. It is formed at a position close to the end surface 13 of the overhang portion 3 in the rotor axial direction.

  FIG. 11 is a plan view around the disk engaging portion according to the first embodiment of the present invention. 11 are formed on the front side and the rear side in the circumferential direction of the rotor with respect to the disk engaging part 6. The stress relaxation part 9e shown in FIG. 11 is an oval hole long in the rotor circumferential direction. With such a configuration, the stress relaxation portion 9e can reduce stress concentration generated in the vicinity of the disk engaging portion 6 on both sides in the rotor circumferential direction with respect to the disk engaging portion 6. Furthermore, as shown in FIG. 11, by making the stress relaxation portion 9e an oval long in the circumferential direction of the rotor, the stress concentration around the disk engagement portion 6 can be reduced as compared with the case where the stress relaxation portion 9 is a perfect circle, for example. It can be further reduced. The positions of the stress relaxation portions 9 formed on the front side and the rear side in the rotor circumferential direction with respect to the disk engaging portion 6 do not necessarily coincide with each other in the rotor axial direction.

(Fourth modification)
FIG. 12 is a plan view around the disc engaging portion of the fourth modified example of the first embodiment of the present invention. A plurality of stress relaxation portions 9 f shown in FIG. 12 are formed on the front side and the rear side in the rotor circumferential direction with respect to the disk engaging portion 6. With such a configuration, the stress relaxation portion 9f further reduces stress concentration generated in the vicinity of the disk engagement portion 6 by the plurality of stress relaxation portions 9 on both sides in the rotor circumferential direction with respect to the disk engagement portion 6. be able to. The positions of the stress relaxation portions 9 formed on the front side and the rear side in the rotor circumferential direction with respect to the disk engaging portion 6 do not necessarily coincide with each other in the rotor axial direction. In FIG. 12, two stress relaxation portions 9f are arranged on the front side and the rear side in the circumferential direction of the rotor, but the number is not limited. Three or more stress relaxation portions 9f may be arranged on the front side and the rear side in the rotor circumferential direction.

(5th modification)
FIG. 13 is a plan view around the disc engaging portion of the fifth modified example of the first embodiment of the present invention. The stress relaxation part 9g shown in FIG. 13 is a perfect hole. Of the inner walls at both axial ends that form the maximum axial width of the hole, the stress relaxation portion 9g has an inner wall on the side farther from the opposite end surface 13 of the projecting portion 3 in the rotor axial direction. 6 of the inner walls at both ends in the axial direction forming the maximum axial width of 6 and the inner wall nearer in the rotor axial direction from the opposite end face 13 of the projecting portion 3 and the downstream side in the rotor axial direction of the seal plate 2 disposed in the groove portion 4. It is preferably arranged between the side edges 15.

  Here, generally, a case where the disk engaging portion 6 is not provided in the overhang portion 3 is considered. Due to the centrifugal force generated by the rotation of the rotor disk 60, circumferential stress is generated in the overhang portion 3 in the circumferential direction of the rotor. Next, consider a case where the disk engaging portion 6 is provided in the overhang portion 3. The circumferential stress is concentrated around the disk engaging portion 6 so as to avoid the disk engaging portion 6. Stress concentration generated around the hole-shaped disk engaging portion 6 is caused on the end surface 13 of the protruding portion 5 facing the rotor axial direction in the vicinity of the inner walls at both ends in the axial direction forming the maximum axial width of the disk engaging portion 6. It is considered to be the largest on the near inner wall.

  Therefore, with such a configuration, the stress relaxation portion 9g has a tension in the vicinity of the inner walls at both ends in the axial direction that form the maximum axial width of the hole-shaped disk engaging portion 6 where stress concentration occurs. Stress concentration in the vicinity of the inner wall near the end face 13 of the protruding portion 3 can be reduced. Of the inner walls at both ends in the axial direction forming the maximum axial width of the hole, one inner wall far from the end face 13 of the projecting portion 3 is in the rotor axial direction of the seal plate engaging portion 7 disposed in the groove portion 4. By being located closer to the end face 13 of the protruding portion 5 than the downstream side edge 15, the stress relaxation portion 9g and the seal plate 2 overlap in the radial direction of the rotor, and the sealing performance of the seal structure 1 is maintained.

(Sixth Modification)
FIG. 14 is a plan view around the disc engaging portion of the sixth modified example of the first embodiment of the present invention. The stress relaxation portion 9h shown in FIG. 14 may be an arc-shaped notch formed in the rotor axial direction from the end surface 13 of the overhang portion 3. In this case, the inner wall farthest from the end surface 13 of the protruding portion 5 that forms the axially deepest portion of the notch is the inner wall at both axial ends that forms the maximum axial width of the hole-shaped disk engaging portion 6. Of these, the inner wall of the projecting portion 5 near the end surface 13 and the side edge 15 on the downstream side in the rotor axial direction of the seal plate engaging portion 7 disposed in the groove portion 4 are preferably disposed.

  As described above, the stress concentration around the hole-shaped disk engaging portion 6 is close to the end surface 13 of the protruding portion 5 facing the rotor axial direction in the vicinity of the inner walls at both axial ends forming the maximum axial width. It is considered to be the largest on the inner wall.

  Therefore, with such a configuration, the stress relaxation portion 9h is formed on the protruding portion 5 of the inner walls at both ends in the axial direction that form the maximum axial width of the hole-shaped disk engaging portion 6 where stress concentration occurs. Stress concentration near the inner wall near the end face 13 can be reduced. Of the inner walls at both axial ends that form the maximum axial width of the hole, one inner wall far from the end face 13 of the protrusion 5 is from the side edge 15 in the axial direction of the seal plate 2 disposed in the groove 4. Further, by disposing at a position close to the end face 13 of the protruding portion 5, the stress relaxation portion 9h and the seal plate 2 overlap in the rotor radial direction, and the sealing performance of the seal structure 1 is maintained.

(Second Embodiment)
A second embodiment of the seal structure according to the present invention will be described with reference to FIGS. As in the first embodiment, the seal structure 101 according to the second embodiment is provided on the rotor disk 60 and has an overhang portion 3 provided with the groove portion 4, the seal plate 2 inserted into the groove portion 4, and A detent member 28 is provided.

  As shown in FIG. 15, the seal plate 2 is fixed by a non-rotating member 28, and is disposed in a groove portion 4 provided in the protruding portion 3 of the rotor disk 60. As in the first embodiment, the seal plate 2 is a member in which at least two annular plates are slightly shifted in the circumferential direction and overlapped in the radial direction and fixed by a rotation stop member 28. The seal plate 2 rotates in close contact with the protruding portion 5 by the centrifugal force generated by the rotation of the rotor disk 60. Therefore, the combustion gas is sealed at the close contact surface of the seal plate, and the combustion gas can be further prevented from flowing into the interior. For the same reason, it is possible to prevent the cooling medium inside the rotor from flowing out from the seal plate 2 to the gas path side.

  The number and arrangement of the disk engaging portion 26, the seal plate engaging portion 27, and the anti-rotation member 28 are the same as those in the first embodiment. However, instead of providing the arc-shaped seal plate engaging portion 7 at the side edge 15 of the seal plate 2 in the first embodiment, in the second embodiment, the seal plate engaging portion is formed as a hole penetrating the vicinity of the side edge 15. 27 is provided.

  In the first embodiment, the disk engaging portion 6 is disposed as a hole penetrating the protruding portion 3 in the rotor radial direction. However, in the second embodiment, the disk engaging portion 26 is extended. The end surface 13 of the part 3 is provided in a groove shape.

  Specifically, as shown in FIGS. 16 and 17, the disk engaging portion 26 can accommodate a detent member 28 over a predetermined length from the end surface 13 of the overhang portion 3 in the rotor axial direction. With a large size, it is formed as a notch that penetrates the overhanging portion 3 from the outside in the rotor radial direction toward the inside.

  The anti-rotation member 28 may include a gripping member, an intermediate holding member, and a fixing screw. The seal plate 2 is provided with a seal plate engaging portion 27 opened in a hole shape for inserting a fixing screw. The gripping member is formed in a U shape and sandwiches the seal plate 2 between two opposing gripping portions. Screw holes that can accept fixing screws are opened in the upper and lower gripping portions, and an intermediate holding member is fitted in accordance with the seal plate engaging portion 27 of the seal plate 2. Further, the fixing plate is inserted through the screw hole from the inner side in the rotor radial direction, and the seal plate 2 is fixed. Furthermore, since the seal plate is fixed via the intermediate holding member, the seal plate does not directly contact the fixing screw, and even if the seal plate 2 moves relatively, there is no possibility of damaging the screw portion of the fixing screw. The anti-rotation member 28 is inserted into a hole-like seal plate engaging portion 27 provided in the seal plate 2, and the anti-rotation member 28 is accommodated in the disk engaging portion 26 from the inside of the rotor, so that the seal plate 2 is placed in the groove portion 4. The seal plate 2 is assembled so as to be inserted into With such a configuration, the seal plate 2 is fixed to the rotor disk 60 via the seal plate engaging portion 27, the anti-rotation member 28 and the disk engaging portion 26, and the rotor axial direction and the rotor are within the groove portion 4. Circumferential movement is constrained.

  The stress relaxation part 9 is arrange | positioned at the protrusion part 5 so that it may overlap with the radial direction of a rotor with respect to the seal plate 2, as shown in FIG. 16, FIG. With such a configuration, in order to reduce stress concentration around the disk engaging portion 26, the sealing performance of the seal structure 101 is maintained even if the stress relaxation portion 9 is provided in the protruding portion 5.

  According to the above-described configuration, the seal plate 2 is locked by the anti-rotation member 28 via the seal plate engaging portion 27 provided on the seal plate 2, and the anti-rotation member 28 is further attached to the overhang portion 3. It is locked to the overhanging portion 3 of the rotor disc 60 via the provided disc engaging portion 26. Accordingly, the seal plate 2 is locked with respect to the rotor disk 60. Therefore, relative movement of the seal plate 2 in the rotor axial direction and the rotor circumferential direction is suppressed, and wear and replacement frequency of the seal plate 2 are reduced.

  Furthermore, the stress relieving portion 9 is arranged so as to be adjacent to the disk engaging portion 26 in the rotor circumferential direction and to overlap the seal plate 2 in the rotor radial direction, so that the sealing performance of the seal structure 101 is maintained. However, stress concentration around the disk engaging portion 26 can be reduced. Therefore, it is possible to improve the operational life of the members of the seal structure 101 while maintaining the sealing performance of the seal structure 101.

  Although the present embodiment has been described above, the present embodiment is not limited to the above-described content. In addition, the components of the present embodiment described above include those that can be easily assumed by those skilled in the art, those that are substantially the same, and those in a so-called equivalent range. Furthermore, the above-described components can be appropriately combined. In addition, various omissions, substitutions, and changes of the constituent elements can be made without departing from the scope of the present embodiment.

  The seal plate 2 is formed by overlapping a plurality of plates in an annular shape. Although the above-described seal plate 2 has a detachable structure, the seal plate 2 may be fixed to each other via a fixing pin fixed to the seal plate 2 by welding in order to prevent displacement of the rotor between the members in the circumferential direction. The seal plate 2 having such a configuration is inserted into the groove portion 4 of the overhang portion 3 and integrated into the rotor disk 60 as a unit.

DESCRIPTION OF SYMBOLS 1,101 Seal structure 2 Seal plate 3 Overhang | projection part 4 Groove part 5 Protrusion part 6, 26 Disc engagement part 7, 27 Seal plate engagement part 8, 28 Anti-rotation member 9, 9a, 9b, 9c, 9d, 9e, 9f, 9g, 9h Stress relaxation part 11 Radial outer protrusion part 12 Radial inner protrusion part 13 End face 14 Bottom face 15 Side edge 35 Non-rotating pin 36 Holding ring 37 Step part 51 Compressor 52 Combustor 53 Turbine 54 Generator 55 Gas path 56 Combustion gas 57 Cooling medium 58 Rotor shaft 60 Rotor disk

Claims (10)

An overhang portion disposed between a plurality of rotor disks arranged in the rotor axis direction, extending in the rotor axis direction so as to face each other from the adjacent rotor disks, and having an annular groove formed on the opposite end face; ,
An annular seal plate disposed in the circumferential direction of the rotor in the groove and having a seal plate engaging portion formed on a side edge;
A detent member that is locked to the overhanging portion via a disk engaging portion formed in the overhanging portion and that locks the seal plate through the sealing plate engaging portion. ,
The overhanging portion is an annular projecting portion with a tip in the rotor axial direction sandwiching the groove portion,
The projecting portion is provided with a stress relaxation portion adjacent to the disk engaging portion in the rotor circumferential direction,
A gas turbine provided with a seal structure, wherein the stress relaxation portion is arranged so as to overlap with the seal plate in a rotor radial direction. The protrusion has a radially outer protrusion that is radially outer than the seal plate, and a radially inner protrusion that is radially inner than the seal plate,
2. The gas turbine having a seal structure according to claim 1, wherein the stress relaxation portion is formed on at least one of the radially outer projecting portion and the radially inner projecting portion.   3. The gas turbine having a seal structure according to claim 2, wherein the stress relaxation portion penetrates the radially outer projecting portion and the radially inner projecting portion in the rotor radial direction.   The said stress relaxation part is equipped with the seal structure of Claim 2 which penetrates any one of the said radial direction outer side protrusion part or the said radial direction inner side protrusion part among the said protrusion parts in a rotor radial direction. Gas turbine.   3. The gas turbine having a seal structure according to claim 2, wherein the stress relaxation portion is formed only in a radially outer protruding portion of the protruding portions.   6. The gas turbine having a seal structure according to claim 1, wherein the stress relaxation portion is formed on a front side and a rear side in a rotor circumferential direction with respect to the disk engaging portion.   The gas turbine having a seal structure according to claim 1, wherein the stress relaxation portion is an oval hole that is long in a circumferential direction of the rotor.   8. The gas turbine having a seal structure according to claim 1, wherein a plurality of the stress relaxation portions are respectively formed on the front side and the rear side in the rotor circumferential direction with respect to the disk engaging portion.   The stress relieving part is a hole, and of the inner walls at both ends in the axial direction forming the maximum axial width of the hole, the inner wall on the side farther in the rotor axial direction from the opposed end surface is the hole-shaped disk engagement The inner wall at both ends in the axial direction forming the maximum axial width of the portion is disposed between the inner wall near the end surface and the side edge of the seal plate disposed in the groove portion. A gas turbine comprising the seal structure according to 1 to 8.   The stress relaxation portion is a notch formed in the axial direction of the rotor from the end surface of the overhang portion, and an inner wall farthest from the end surface that forms the axially deepest portion of the notch is a hole-like disk engaging member. It is arrange | positioned between the inner wall near the said end surface among the inner walls of the axial direction both ends which form the axial direction maximum width of a joint part, and the said side edge of the said sealing plate arrange | positioned in the said groove part. A gas turbine comprising the seal structure according to any one of Items 1 to 8.

Images