Turbine rotor and gas turbine comprising same
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- MITSUBISHI POWER LTD
- Filing Date
- 2025-10-28
- Publication Date
- 2026-08-06
Smart Images
Figure JP2025037804_06082026_PF_FP_ABST
Abstract
Description
Turbine rotor and gas turbine including the same
[0001] The present invention relates to a turbine rotor and a gas turbine including the same. This application claims priority based on Japanese Patent Application No. 2025-016115 filed in Japan on February 3, 2025, and incorporates the contents herein.
[0002] The gas turbine includes a compressor that compresses air to generate compressed air, a combustor that burns fuel in the compressed air to generate fuel gas, and a turbine that is driven by the combustion gas. The turbine includes a turbine rotor that rotates about an axis, a turbine casing that covers the turbine rotor, and a plurality of stator blade rows.
[0003] For example, Patent Document 1 below discloses a turbine rotor of a gas turbine. This turbine rotor has a plurality of disk units arranged in the axial direction in which the axis extends, and a spindle bolt that extends in the axial direction and couples the plurality of disk units to each other. Here, for the convenience of the following description, the direction perpendicular to the axis is the radial direction, the side approaching the axis in this radial direction is the radially inner side, and the side moving away from the axis in this radial direction is the radially outer side. Further, one side in the axial direction is the upstream side of the axis, and the other side is the downstream side of the axis.
[0004] One disk unit has one rotor disk and one row of moving blades attached to the outer peripheral portion of the rotor disk. One row of moving blades has a plurality of moving blades arranged in the circumferential direction with respect to the axis. One disk unit further includes a lid member provided for each of the plurality of moving blades and attached to the rotor disk, and a plurality of seal plates.
[0005] Each of the plurality of moving blades forms an airfoil shape and has a blade body extending in the radial direction with respect to the axis, a platform provided at the end on the radially inner side of the blade body, a shank provided on the radially inner side of the platform, and a blade root provided on the radially inner side of the shank. Each of the plurality of moving blades further has a blade cooling air passage formed continuously in the blade root, shank, platform, and blade body. This blade cooling air passage opens at the root bottom surface of the blade root and the blade surface of the blade body.
[0006] The rotor disc has a cylindrical small-diameter section centered on its axis and a cylindrical large-diameter section centered on its axis with a larger outer diameter than the small-diameter section. The small-diameter section is connected to the large-diameter section downstream of its axis. The small-diameter section has passage grooves for each of the multiple rotor blades. The passage grooves are recessed radially inward from the outer circumferential surface of the small-diameter section, with an opening at the radially outer edge, and extend toward the large-diameter section in an insertion direction including the axial direction.
[0007] The large-diameter section has a wing groove for each of the multiple rotor blades. The wing groove is recessed from the radially outer to the radially inward section of the large-diameter section, allowing the wing root to be inserted, and extends in the insertion direction, penetrating the large-diameter section. This wing groove has a wing groove bottom surface that faces radially outward and is radially spaced opposite to the root surface of the wing root. This wing groove bottom surface is connected to the bottom surface of the passage groove.
[0008] Each of the multiple sealing plates has a plate body and a projection that faces the downstream end face of the shank of each of the multiple rotor blades and extends circumferentially, sealing the portion downstream of the axis between the shanks of each of the multiple rotor blades. The plate body has an outer peripheral edge that extends circumferentially and faces radially outward, and an inner peripheral edge that extends circumferentially and faces radially inward. The projection protrudes radially inward from the inner peripheral edge of the plate body.
[0009] Each of the multiple rotor blades has a cover member, and each has a seal plate movement restricting groove. The cover member has a cover bottom surface that faces radially inward. The radial position of this cover bottom surface is spaced radially outward from the bottom surface of the passage groove. Within the passage groove, the portion between the cover bottom surface and the bottom surface of the passage groove forms a passage through which cooling air can flow and which connects to the large-diameter blade groove. The seal plate movement restricting groove of the cover member is recessed radially inward from the cover member, and the protruding portion of the seal plate fits into it. The circumferential movement of the seal plate is restricted by the protruding portion of the seal plate fitting into the seal plate movement restricting groove of the cover member.
[0010] Japanese Patent Publication No. 2024-011151
[0011] In the technology described in Patent Document 1, when miniaturizing the lid member, it may not be possible to form a groove to restrict the movement of the seal plate in the lid member. Furthermore, even if it is possible to form a groove to restrict the movement of the seal plate in the lid member, it may not be possible to secure the desired strength in the lid member. For this reason, in the technology described in Patent Document 1, when miniaturizing the lid member, it may not be possible to restrict the circumferential movement of the seal plate with the lid member.
[0012] Therefore, the present disclosure aims to provide a turbine rotor and a gas turbine equipped therewith that can restrict the circumferential movement of the seal plate while keeping manufacturing costs down, even when the cover member is miniaturized.
[0013] A turbine rotor according to one embodiment of the invention for achieving the above objective comprises a rotor disk centered on an axis, a plurality of rotor blades attached to the rotor disk in a circumferential direction with respect to the axis, a cover member provided for each of the plurality of rotor blades and attached to the rotor disk, and a plurality of seal plates. Each of the plurality of rotor blades has an airfoil-shaped cross section perpendicular to the radial direction with respect to the axis and extends in the radial direction, a platform provided at the end of the airfoil on the radially inner side of the airfoil, a shank provided on the radially inner side of the platform and extending in the insertion direction having an axial component in which the axis extends in a virtual plane parallel to the axis, a blade root provided on the radially inner side of the shank and extending in the insertion direction, and a blade cooling air passage formed in connection with the blade root, the shank, the platform, and the airfoil. The shank has a second end face facing the second axis, which is one of two sides facing each other in the axial direction, a first axis side and a second axis side. The blade root has a second end face facing the second axis side and connected to the second end face of the shank, and a base surface facing radially inward. The blade cooling air passage opens at the base surface of the blade root and the blade surface of the blade body. The rotor disc has a cylindrical small-diameter portion centered on the axis and a large-diameter portion that is cylindrical centered on the axis and has an outer diameter larger than the outer diameter of the small-diameter portion. The small-diameter portion is connected to the second axis side of the large-diameter portion. The small-diameter portion has a passage groove for each of the plurality of rotor blades. The passage groove is recessed radially inward from the outer circumferential surface of the small-diameter portion, with its radially outer edge forming an opening, and extends toward the large-diameter portion in the insertion direction. The large-diameter portion has a blade groove for each of the multiple rotor blades. The blade groove is recessed from the radially outer to the radially inward portion of the large-diameter portion so that the blade root can be inserted, and extends in the insertion direction, penetrating the large-diameter portion. The blade groove has a blade groove bottom surface that faces radially outward and is spaced radially apart from the root bottom surface of the blade root. The blade groove bottom surface is connected to the passage groove bottom surface, which is the bottom surface of the passage groove.Each of the plurality of sealing plates has a plate body that faces the second side end face of the shank of the plurality of rotor blades and extends in the circumferential direction, closing the portion on the second axis side between the shanks of each of the plurality of rotor blades, and a recess. The plate body has an outer peripheral edge that faces radially outward and extends in the circumferential direction, and an inner peripheral edge that faces radially inward and extends in the circumferential direction. The recess is recessed radially outward from the inner peripheral edge of the plate body. Each of the plurality of rotor blades has a cover member that closes the opening of the passage groove. The cover body has a cover bottom surface that faces radially inward. The radial position of the cover bottom surface is spaced radially outward with respect to the bottom surface of the passage groove. In the passage groove, the portion between the cover bottom surface and the bottom surface of the passage groove forms a passage through which cooling air can flow and which connects to the blade groove of the large diameter portion. Of the cover members for each of the plurality of rotor blades, at least one cover member, the first cover member, is provided on the cover body and has a fitting portion that fits into the recess of the seal plate.
[0014] A gas turbine according to one embodiment of the invention for achieving the above objective comprises a turbine rotor according to the above embodiment and a turbine casing covering the outer circumference of the turbine rotor.
[0015] According to one aspect of this disclosure, it is possible to restrict the circumferential movement of the seal plate while keeping manufacturing costs down.
[0016] This is a schematic cross-sectional view of a gas turbine in one embodiment of the present disclosure. This is a cross-sectional view of the main part of the final stage disk unit in one embodiment of the present disclosure. This is a detailed cross-sectional view of part III in Figure 2. This is an exploded view of the main part of the final stage disk unit in one embodiment of the present disclosure, when unfolded circumferentially and viewed from the radially outside. This is a cross-sectional view along line V-V in Figure 3 with the lid member omitted. This is a cross-sectional view along line V-V in Figure 3 with the lid member included. This is an exploded perspective view of the main part of the final stage disk unit in one embodiment of the present disclosure. This is a perspective view of the first lid member in one embodiment of the present disclosure. This is a perspective view of the second lid member in one embodiment of the present disclosure. This is a front view of the seal plate in one embodiment of the present disclosure and the seal plate in a comparative example. This is a cross-sectional view of the main part of the lid member in a modified example of one embodiment of the present disclosure.
[0017] Hereinafter, embodiments of the turbine rotor of this disclosure and a gas turbine equipped with this turbine rotor will be described in detail with reference to the drawings.
[0018] "Embodiment of a Gas Turbine" As shown in Figure 1, the gas turbine of this embodiment includes a compressor 10 that compresses air A, a combustor 15 that burns fuel F in the air A compressed by the compressor 10 to generate combustion gas G, and a turbine 20 that is driven by the combustion gas G.
[0019] The compressor 10 includes a compressor rotor 13 that rotates around the axis Ar, a compressor casing 11 that covers the compressor rotor 13, and a plurality of stator blade rows 12. The turbine 20 includes a turbine rotor 23 that rotates around the axis Ar, a turbine casing 21 that covers the turbine rotor 23, and a plurality of stator blade rows 22. In the following, the direction in which the axis Ar extends will be called the axial direction Da, the circumferential direction around this axis Ar will simply be called the circumferential direction Dc, and the direction perpendicular to the axis Ar will be called the radial direction Dr. Also, one side of the axial direction Da will be called the upstream side Dau, and the opposite side will be called the downstream side Dad. Also, the side of the radial direction Dr that approaches the axis Ar will be called the inner radial direction Dri, and the opposite side will be called the outer radial direction Dr.
[0020] The compressor 10 is positioned on the axial upstream side Dau relative to the turbine 20.
[0021] The compressor rotor 13 and the turbine rotor 23 are located on the same axis Ar and are connected to each other to form a gas turbine rotor 3. For example, the rotor of a generator GEN is connected to this gas turbine rotor 3. The gas turbine further includes an intermediate casing 2. This intermediate casing 2 is located in the axial direction Da and is positioned between the compressor casing 11 and the turbine casing 21. A combustor 15 is attached to this intermediate casing 2. The compressor casing 11, the intermediate casing 2, and the turbine casing 21 are connected to each other to form a gas turbine casing 1.
[0022] The compressor rotor 13 has a rotor shaft 13r extending in the axial direction Da with respect to the axis Ar, and a plurality of rotor blade rows 13b attached to this rotor shaft 13r. The plurality of rotor blade rows 13b are arranged in the axial direction Da. Each rotor blade row 13b is composed of a plurality of rotor blades arranged in the circumferential direction Dc. One of a plurality of stator blade rows 12 is positioned on the downstream side Da of each rotor blade row 13b. Each stator blade row 12 is provided inside the compressor casing 11. Each stator blade row 12 is composed of a plurality of stator blades arranged in the circumferential direction Dc.
[0023] The turbine rotor 23 has a plurality of disk units 25 arranged in the axial direction Da, and spindle bolts 26 extending in the axial direction Da and connecting the plurality of disk units 25 to each other. One disk unit 25 has one rotor disk 27 and one rotor blade row 23b attached to the outer circumference of this rotor disk 27. One rotor blade row 23b has a plurality of rotor blades arranged in the circumferential direction Dc with respect to the axis Ar. The rotor disks 27 of each of the plurality of disk units 25 are connected to each other by the aforementioned spindle bolts 26 to form the rotor shaft 23r of the turbine rotor 23. A plurality of stator blade rows 22 are arranged in the axial direction Da and attached to the inner circumference of the turbine casing 21. Each of the plurality of stator blade rows 22 is positioned on the axial upstream side Dau of one of the rotor blade rows 23b of the plurality of disk units 25. Each row of stator vanes 22 has multiple stator vanes arranged in the circumferential direction Dc with respect to the axis Ar.
[0024] Of the multiple disk units 25, the final stage disk unit 25f, which is the disk unit 25 furthest downstream on the axis Da, has, as shown in Figures 2 and 3, a rotor disk 27f, a row of rotor blades 23b attached to this rotor disk 27f, multiple front seal plates 70, front seal plate retaining members 71, multiple rear seal plates 72, multiple cover members 80 for each of the multiple rotor blades 50, multiple cover retaining members 85 for each of the multiple rotor blades 50, and multiple blade root springs 90 for each of the multiple rotor blades 50. Note that Figure 3 is an enlarged view of part III in Figure 2.
[0025] As shown in Figures 4 to 7, the multiple rotor blades 50 constituting the rotor blade row 23b each have a blade body 51, a platform 52, a shank 61, and a blade root 65. Figure 4 is an exploded view of the main part of the final stage disk unit 25f, unfolded in the circumferential direction Dc and viewed from the radially outer side Do. Figure 5 is a cross-sectional view taken along line V-V in Figure 3 with the cover member 80 omitted. Figure 6 is a cross-sectional view taken along line V-V in Figure 3 with the cover member 80 included. Figure 7 is an exploded perspective view of the main part of the final stage disk unit 25f.
[0026] The wing body 51 has an airfoil shape with a cross section perpendicular to the radial direction Dr with respect to the axis Ar, and extends in the radial direction Dr.
[0027] The platform 52 is provided at the end of the wing body 51 on the radially inward side Dri. As shown in Figures 3, 4, and 7, the platform 52 has a gas path surface 53, an anti-gas path surface 54, a front end surface 55 (see Figures 4 and 7), a rear end surface 56, and a pair of side surfaces 57. The gas path surface 53 faces radially outward Dr. The wing body 51 extends radially outward Dr from this gas path surface 53. The anti-gas path surface 54 is back-to-back with the gas path surface 53 and faces radially inward Dri. The front end surface 55 extends radially in Dr and circumferentially in Dc and faces upstream of the axis Dau. The rear end surface 56 is back-to-back with the front end surface 55. This rear end surface 56 extends radially in Dr and circumferentially in Dc and faces downstream of the axis Dad. The rear end surface 56 is parallel to the front end surface 55. Both of the pair of side surfaces 57 extend in the radial direction Dr and the insertion direction Di, and face the circumferential direction Dc. The insertion direction Di is the direction having an axial component Da in a plane parallel to the axis Ar, as shown in Figure 4. Specifically, the insertion direction Di in this embodiment is the direction forming a narrow angle with respect to the axis Ar in a plane parallel to the axis Ar. The pair of side surfaces 57 are parallel to each other. Therefore, when viewed from the radial direction Dr, the platform 52 has a parallelogram shape. The platform 52 further has a front seal plate groove 58 and a rear seal plate groove 59. The front seal plate groove 58 is formed in the part of the platform 52 closer to the front end surface 55. The rear seal plate groove 59 is formed in the part of the platform 52 closer to the rear end surface 56. Both the front seal plate groove 58 and the rear seal plate groove 59 are recessed radially outward from the anti-gas pass surface 54 towards Dr and extend in the circumferential direction Dc.
[0028] The shank 61 is provided on the radially inward side Dri of the platform 52 and extends in the insertion direction Di. The shank 61 has a front end face 62 (see Figure 7), a rear end face (or second side end face) 63, and a pair of side faces 64. The front end face 62 widens radially in the Dr and circumferentially in the Dc direction and faces upstream of the axis Dau. The rear end face 63 is back-to-back with the front end face 62. This rear end face 63 widens radially in the Dr and circumferentially in the Dc direction and faces downstream of the axis Dad. The rear end face 63 is parallel to the front end face 62. Both of the pair of side faces 64 widen radially in the Dr and in the insertion direction Di and face circumferentially in the Dc direction. The distance between the pair of side faces 64 in the circumferentially in the Dc direction gradually narrows towards the radially inward side Dri, as shown in Figure 5.
[0029] The wing root 65 is located radially inward (Dri) of the shank 61 and extends in the insertion direction (Di). The wing root 65 has a front end face 66 (see Figure 7), a rear end face (or second side end face) 67, a base face 65b, and a pair of side faces 68. The front end face 66 extends radially (Dr) and circumferentially (Dc), and faces upstream (Dau) along the axis. This front end face 66 is connected to the front end face 62 of the shank 61. The rear end face 67 is back-to-back with the front end face 66. This rear end face 67 extends radially (Dr) and circumferentially (Dc), and faces downstream (Dad) along the axis. The rear end face 67 is parallel to the front end face 66. This rear end face 67 is connected to the rear end face 63 of the shank 61. The base surface 65b is located in the radially innermost direction (Dri) within the wing root 65 and faces radially inward (Dri). Both of the pair of side surfaces 68 extend radially (Dr) and in the insertion direction (Di). As shown in Figure 5, the wing root 65 is formed such that the width between the pair of side surfaces 68 alternates between a wide portion and a narrow portion. In other words, the cross-sectional shape of the wing root 65 perpendicular to the insertion direction (Di) is Christmas tree shaped. For the sake of the following explanation, the portion with the widest width between the pair of side surfaces 68, which is radially inward (Dri), will be referred to as the first wide portion 65f. The aforementioned base surface 65b is the surface within the first wide portion 65f that faces radially inward (Dri).
[0030] The rotor blade 50 further has a blade cooling air passage 69. The blade cooling air passage 69 extends within the blade root 65, shank 61, platform 52, and blade body 51. One end of the blade cooling air passage 69 opens at the base surface 65b of the blade root 65, and the other end opens at the blade surface of the blade body 51.
[0031] As shown in Figure 2, the rotor disk 27f of the final stage disk unit 25f has a cylindrical rear shaft portion 28 centered on the axis Ar, a first small diameter portion 31 that is cylindrical centered on the axis Ar and has an outer diameter larger than the outer diameter of the rear shaft portion 28, a second small diameter portion 34 that is cylindrical centered on the axis Ar and has an outer diameter larger than the outer diameter of the first small diameter portion 31, and a large diameter portion 41 that is cylindrical centered on the axis Ar and has an outer diameter larger than the outer diameter of the second small diameter portion 34. The first small diameter portion 31 is connected to the axial upstream side Dau of the rear shaft portion 28. The second small diameter portion 34 is connected to the axial upstream side Dau of the first small diameter portion 31. The large diameter portion 41 is connected to the axial upstream side Dau of the second small diameter portion 34. In this embodiment, the first axis Da1 is the upstream axis Dau, and the second axis Da2 is the downstream axis Dad.
[0032] The rear shaft portion 28 has a main cooling air passage 29 through which cooling air Ac can flow. The main cooling air passage 29 extends from the rear end face (not shown) of the rear shaft portion 28 toward the upstream side Dau of the axis into the second small diameter portion 34.
[0033] The first small-diameter section 31 has a plurality of first radial passages 32 and a plurality of axial passages 33. The first radial passages 32 extend radially Dr within the first small-diameter section 31. The radially inner end of each first radial passage 32 is connected to the axially upstream end Dau of the main cooling air passage 29. The axial passages 33 extend radially from the radially outer end of each first radial passage 32 toward the axially upstream end Dau into the first small-diameter section 31.
[0034] The second small-diameter section 34 (hereinafter sometimes simply referred to as the small-diameter section) has a plurality of second radial passages 35, a plurality of passage grooves 36, a seal plate groove 37, and a lid retaining groove 38, as shown in Figures 3 to 7. The plurality of second radial passages 35 and the plurality of passage grooves 36 are present for each of the plurality of rotor blades 50. The second radial passage 35 (hereinafter sometimes simply referred to as the radial passage) extends radially Dr within the second small-diameter section 34. The radially inner end of this second radial passage 35 is connected to the axial upstream end Dau of the axial passage 33 in the first small-diameter section 31, as shown in Figure 2. The passage groove 36 is recessed radially inward Dr from the outer circumferential surface of the second small-diameter section 34, with its radially outer edge Dau forming an opening, and extends radially outward Di toward the axial upstream end Dau from the radially outer end Dau of the second radial passage 35. The seal plate groove 37 is formed in the second small diameter portion 34 at the boundary with the large diameter portion 41. This seal plate groove 37 is recessed from the radially outer Dr to the radially inner Dri and extends in the circumferential direction Dc. The groove depth of this seal plate groove 37 is shallower than the groove depth of the passage groove 36. The lid retaining groove 38 is formed in the second small diameter portion 34 at a position Da downstream of the axis of the multiple second radial passages 35, as shown in Figures 3 and 4. This lid retaining groove 38 is recessed from the radially outer Dr to the radially inner Dri and extends in the circumferential direction Dc. The groove depth of this seal plate groove 37 is also shallower than the groove depth of the passage groove 36.
[0035] As shown in Figures 3 to 7, the large-diameter section 41 has a wing groove 42 for each of the multiple rotor blades 50. The wing groove 42 is recessed radially inward (Dri) from the outer circumferential surface 41o of the large-diameter section 41, extends in the insertion direction (Di) and penetrates the large-diameter section 41. The wing groove 42 has a Christmas tree shape in its cross-sectional shape perpendicular to the insertion direction (Di), similar to the wing root 65, so that the wing root 65 of the rotor blade 50 can be fitted into it. Here, for the sake of the following explanation, the portion with the largest width between the sides of a pair of grooves, the portion with the largest radially inward (Dri) is referred to as the first wide section 42f (see Figure 5). The surface located in the radially inward (Dri) of this first wide section 42f and facing radially outward (Do) forms the bottom surface 42b of the wing groove 42. The radial Dr dimension of the first wide portion 42f of the blade groove 42 is larger than the radial Dr dimension of the first wide portion 65f of the blade root 65. Therefore, when the blade root 65 is fitted into the blade groove 42, an insertion-direction passage 43 is formed between the root base surface 65b and the blade groove bottom surface 42b, which is a passage through which cooling air can flow. A blade root spring 90 is positioned in this insertion-direction passage 43. This blade root spring 90 has a C-shaped cross-section perpendicular to the axial direction Da. This blade root spring 90 contacts the root base surface 65b and the blade groove bottom surface 42b, pushing the rotor blade 50 radially outward Dr. The cross-sectional shape of the passage groove 36 in the second small diameter portion 34 perpendicular to the insertion direction Di coincides with the cross-sectional shape of the first wide portion 42f in the blade groove 42 perpendicular to the insertion direction Di, and the bottom surface of the passage groove 36b, which is the bottom surface of the passage groove 36, is connected to the bottom surface of the blade groove 42b.
[0036] As shown in Figure 2, each of the multiple front seal plates 70 faces the front end surface 62 of the shank 61 of the multiple rotor blades 50 and extends in the circumferential direction Dc, so that it can close the portion of the shank 61 between each of the multiple rotor blades 50 on the upstream side Dau of the axis. The radially outer portion of this front seal plate 70, Dr, fits into the front seal plate groove 58 of the platform 52. The radially inner portion of this front seal plate 70, Dr, is restrained by the front seal plate retaining member 71 so that it cannot move relative to the rotor disk 27f.
[0037] Each of the multiple rear sealing plates 72 has a plate body 73 and a recess 74, as shown in Figures 3 to 7. The plate body 73 faces the rear end face (second side end face) 63 of the shank 61 and extends in the circumferential direction Dc, so that it can close the portion of the axis downstream Da (second side Da2) between the shanks 61 of each of the multiple rotor blades 50. For this reason, the length of the plate body 73 in the circumferential direction Dc is long enough to face at least the rear end face (second side end face) 63 of the shank 61 of two adjacent rotor blades 50 in the circumferential direction Dc. The plate body has an outer peripheral edge 73o that faces radially outward Dr and extends in the circumferential direction Dc, and an inner peripheral edge 73i that faces radially inward Dri and extends in the circumferential direction Dc. The recess 74 is recessed from the inner peripheral edge 73i of the plate body 73 toward radially outward Dr. The outer peripheral edge 73o of the plate body 73 fits into the rear seal plate groove 59 of the platform 52. The inner peripheral edge 73i of the plate body 73 fits into the seal plate groove 37 of the second small diameter portion 34.
[0038] As shown in Figures 3 to 9, the lid member 80 is a component independent of the rotor blade 50 and is a component that fits into the passage groove 36 of the second small diameter portion 34 and can close the opening 36o of the passage groove 36. As mentioned above, the passage groove 36 is a groove that extends in the insertion direction Di. For this reason, the lid member 80 is also a component that extends in the insertion direction Di. Each of the multiple lid members 80 has a lid body 81 that closes the opening 36o of the passage groove 36 and faces the inner peripheral edge 73i of the plate body 73. The lid body 81 has a front end surface 81f facing the upstream side of the axis Dau (first side of the axis Da1), a rear end surface (second side end surface) 81r facing the downstream side of the axis Dad (second side of the axis Da2), a lid bottom surface 81b facing the radially inward Dri, a plate-facing surface 84 facing the radially outward Dr and facing the inner peripheral edge 73i of the plate body 73, and a tool hole 82 that is recessed from the radially outward Dr toward the radially inward Dri.
[0039] When the lid body 81 is fitted into the passage groove 36 and the opening 36o of the passage groove 36 is closed, the front end surface 81f of the lid body 81 faces the portion of the first wide portion 65f in the rear end surface (second side end surface) 67 of the wing root 65 in the insertion direction Di. Also, in this state, the lid bottom surface 81b is located radially inward Dri from the root bottom surface 65b. Therefore, a part of the front end surface 81f of the lid body 81 faces the rear end surface (second side end surface) 67 of the wing root 65 in the insertion direction Di. The cross-sectional shape of the lid body 81 perpendicular to the insertion direction Di basically corresponds to the cross-sectional shape of the first wide portion 65f of the wing root 65 perpendicular to the insertion direction Di. As mentioned above, the cross-sectional shape of the passage groove 36 perpendicular to the insertion direction Di coincides with the cross-sectional shape of the first wide portion 42f in the wing groove 42 perpendicular to the insertion direction Di. Therefore, when the lid member 80 is fitted into the passage groove 36, a passage in the insertion direction 39 is formed between the lid bottom surface 81b and the passage groove bottom surface 36b, allowing cooling air to flow through and communicating with the insertion direction passage 43 between the root bottom surface 65b and the wing groove bottom surface 42b. Furthermore, when the lid member 80 is fitted into the passage groove 36 of the second small diameter portion 34, the lid member 80 can no longer move relative to the second small diameter portion 34 in the radially outward direction (Dro).
[0040] Here, as shown in Figure 8, a virtual plane extending in a direction perpendicular to the insertion direction Di is simply referred to as the virtual plane VP. Within the inner circumferential surface of the tool hole 82, the surface that faces the upstream side Dau (first side Da1) of the axis and extends in a direction having a component in the direction of expansion of this virtual plane VP forms the tool engagement surface 82p. That is, this tool engagement surface 82p is a surface that faces the upstream side Dau (first side Da1) of the axis and extends in a direction having a component in the direction perpendicular to the insertion direction Di.
[0041] As shown in Figure 4, among the multiple lid members 80, some of the lid members are first lid members 80A, and the remaining plate members are second lid members 80B. The first lid members 80A and the second lid members 80B are arranged alternately in the circumferential direction Dc. As shown in Figure 8, the first lid member 80A has a fitting portion 83 that protrudes radially outward Doro from the plate-facing surface 84 of the lid body 81 and fits into the recess 74 of the rear seal plate 72. On the other hand, as shown in Figure 9, the second lid member 80B does not have the fitting portion 83 of the first lid member. That is, the second lid member 80B does not have a portion that protrudes radially outward Doro from the plate-facing surface 84 of the lid body 81.
[0042] As shown in Figures 3, 4, and 7, the lid retaining member 85 has a first retaining member 86 present for each of the multiple rotor blades 50, a multiple second retaining member 87, and a spacing changing member 88 present for each of the multiple rotor blades 50. The first retaining member 86 is a plate-shaped member that can contact the rear end surface 81r of the lid body 81. The second retaining member 87 is a plate-shaped member that extends in the circumferential direction Dc and is positioned on the downstream side Da (second side Da2 of the axis) of the first retaining member 86. The spacing changing member 88 is a male screw. The first retaining member 86 and the second retaining member 87 each have female screws 86s and 87s that penetrate in the axial direction Da and into which the male screw spacing changing member 88 can be screwed. However, the female screw 87s of the second retaining member 87 is a reverse thread with respect to the female screw 86s of the first retaining member 86. Therefore, after screwing the male threaded spacing changer 88 into the female threads 86s of the first stopper member 86 and the female threads 87s of the second stopper member 87, rotating the male threaded spacing changer 88 changes the axial spacing Da between the first stopper member 86 and the second stopper member 87.
[0043] Next, the assembly order of the final-stage disk unit 25f described above will be explained. First, the blade groove 42 of the rotor disk 27f and the blade root 65 of the moving blade 50 are opposed in the insertion direction Di. Then, the moving blade 50 is moved in the insertion direction Di, and the blade root 65 of the moving blade 50 is fitted into the blade groove 42 of the rotor disk 27f. Then, in the blade groove 42, a blade root spring 90 elastically compressed in the radial direction Dr is inserted between the root bottom surface 65b and the blade groove bottom surface 42b. Note that after inserting the blade root spring 90 into the blade groove 42, the blade root 65 of the moving blade 50 may be inserted into this blade groove 42.
[0044] Next, the front seal plate 70 and the rear seal plate 72 are attached to the rotor disk 27f. When attaching the rear seal plate 72, the rear seal plate 72 is moved in the circumferential direction Dc, the outer peripheral edge 73o of the plate body 73 in the rear seal plate 72 is fitted into the rear seal plate groove 59 of the moving blade 50, and the inner peripheral edge 73i of the plate body 73 in the rear seal plate 72 is fitted into the seal plate groove 37 of the second small-diameter portion 34. At this time, the rear seal plate 72 is moved in the circumferential direction Dc so that the recess 74 of the rear seal plate 72 is in the same position as one of the plurality of passage grooves 36 of the second small-diameter portion 34 in the circumferential direction Dc.
[0045] Next, the front end face 81f of the lid member 80 and the passage groove 36 of the second small-diameter portion 34 are opposed in the insertion direction Di. Then, the lid member 80 is moved in the insertion direction Di, the lid member 80 is fitted into the passage groove 36, and the front end face 81f of the lid member 80 is opposed to the rear end face 67 of the blade root 65 and a part of the blade root spring 90 in the insertion direction Di. When the lid member 80 is fitted into the passage groove 36, the lid member 80 becomes immovable relative to the second small-diameter portion 34 in the radial direction Dr. Also, when the first lid member 80A is fitted into the passage groove 36, the fitting portion 83 of the first lid member 80A is fitted into the recess 74 of the rear seal plate 72, and the rear seal plate 72 becomes immovable in the circumferential direction Dc. Further, when the second lid member 80B is fitted into the passage groove 36, the plate opposing surface 84 of the second lid member 80B faces the inner peripheral edge 73i of the rear seal plate 72 in the radial direction Dr, and the movement of the rear seal plate 72 in the radial direction Dr is restricted.
[0046] Next, a spacing change member 88, which is a male screw, is screwed into the female screw 86s of the first stopper member 86 and the female screw 87s of the second stopper member 87 so that the distance between the first stopper member 86 and the second stopper member 87 is minimized, and the first stopper member 86 and the second stopper member 87 are connected by the spacing change member 88. Next, the first stopper member 86 and the second stopper member 87 connected by the spacing change member 88 are inserted into the lid retaining groove 38 of the second small-diameter portion 34. Then, the spacing change member 88, which is a male screw, is rotated to widen the distance between the first stopper member 86 and the second stopper member 87, bring the first stopper member 86 into contact with the rear end face 81r of the lid member 80, and bring the front end face 81f of this lid member 80 into contact with the rear end face 67 of the blade root 65. As a result, the lid member 80 becomes immovable in the insertion direction Di.
[0047] With the above steps, the assembly of the final-stage disk unit 25f is completed.
[0048] In the radially outer Dr o of the platform 52 in the moving blade 50 for each of the plurality of moving blade rows 23b, combustion gas G from the combustor 15 flows into the annular combustion gas flow path on the radially inner Dri of the turbine casing 21. In this combustion gas flow path, there is a blade body 51 of the moving blade 50.
[0049] In this final-stage disk unit 25f, cooling air Ac is supplied into the main cooling air passage 29 of the rear shaft portion 28. The cooling air Ac flows from the main cooling air passage 29 through the first radial passage 32 and the axial passage 33 of the first small-diameter portion 31 into the second radial passage 35 of the second small-diameter portion 34. The cooling air Ac flows from this second radial passage 35 through an insertion direction passage 39 formed by the passage groove 36 of the second small-diameter portion 34 and the lid member 80 into an insertion direction passage 43 in the blade groove 42. The cooling air Ac that has flowed into the insertion direction passage 43 in the blade groove 42 flows into the blade cooling air passage 69 of the moving blade 50 and cools the blade body 51 of this moving blade 50.
[0050] In this embodiment, the rear seal plate 72 has a recess 74 that is recessed radially outward from the inner peripheral edge 73i of the plate body 73 toward Dr. Furthermore, the first lid member 80A in this embodiment has a fitting portion 83 that fits into the recess 74 of the seal plate 72. Therefore, in this embodiment, the movement of the rear seal plate 72 in the circumferential direction Dc can be restricted. Moreover, in this embodiment, there is no need to form a groove in the lid member 80 that is recessed radially inward toward Dr., so even when the lid member 80 is miniaturized, the movement of the seal plate 72 in the circumferential direction Dc can be restricted as described above.
[0051] Here, in order to explain other effects of this embodiment, a comparative example will be described with reference to Figure 10. In this comparative example, the seal plate 72C has a protrusion 74C that projects radially inward Dri from the inner peripheral edge 73i of the plate body 73C. In this relationship, the lid member has a groove that is recessed toward radially inward Dri so that the protrusion 74C of the seal plate 72C can fit into it. When manufacturing this seal plate 72C, first a material plate 75C is prepared. The thickness of this material plate 75C is the same as the thickness of the seal plate 72C in the comparative example. The circumferential length Dc of this material plate 75C is the same as the circumferential length Dc of the seal plate 72C in the comparative example. The radial length Dr LC of this material plate 75C is the length obtained by adding the radial length Dr L of the protrusion 74C to the radial length Dr L of the plate body 73 in the comparative example. Then, the portion 76C of the radially inner Dri of the material plate 75C, excluding the portion that will become the protruding portion 74C, is removed to complete the seal plate 72C.
[0052] In manufacturing the seal plate 72 in this embodiment, first, a base plate 75 is prepared. The thickness of this base plate 75 is the same as the thickness of the seal plate 72 in this embodiment. The length of the base plate 75 in the circumferential direction Dc is the same as the length of the seal plate 72 in the circumferential direction Dc in this embodiment. The length L of the base plate 75 in the radial direction Dr is the same as the length L of the plate body 73 in this embodiment. Then, the portion 76 that will become the recess 74 is removed from the radially inner Dri portion of this base plate 75 to complete the seal plate 72.
[0053] In this embodiment, the radial length Dr L of the plate body 73 is the same as the radial length Dr L of the plate body 73C in the comparative example. Therefore, the radial length Dr L of the material plate 75 prepared in this embodiment is shorter than the radial length Dr LC of the material plate 75C prepared in the comparative example. Furthermore, in manufacturing the seal plate 72, in this embodiment, the amount of portion 76 removed from the material plate 75 is less than the amount of portion 76C removed from the material plate 75C in the comparative example. Therefore, in this embodiment, material costs can be reduced, and the amount of material waste can also be reduced.
[0054] As described above, in this embodiment, even when the lid member 80 is miniaturized, it is possible to restrict the movement of the sealing plate 72 in the circumferential direction Dc while keeping manufacturing costs down.
[0055] Incidentally, within the fitting portion 83 of the first lid member 80A, the radial movement of the seal plate 72 in the radial direction Dr can be restricted by the surface facing radially outward Dr. However, if a part of the fitting portion 83 of the first lid member 80A is worn away during the process of repeatedly attaching and removing the first lid member 80A, the first lid member 80A cannot sufficiently restrict the radial movement of the seal plate 72 in the radial direction Dr. In this embodiment, even if a part of the fitting portion 83 of the first lid member 80A is worn away, the plate-facing surface 84 of the second lid member 80B can restrict the radial movement of the seal plate 72 in the radial direction Dr.
[0056] The length of the plate body 73 of the seal plate 72 in the circumferential direction Dc is such that it can face two adjacent lid members 80 in the circumferential direction Dc, but cannot face three lid members 80 that are adjacent to each other in the circumferential direction Dc. Even in this case, in this embodiment, since the first lid member 80A and the second lid member 80B are arranged alternately in the circumferential direction Dc, the movement of the seal plate 72 in the circumferential direction Dc and the radial direction Dr can be restricted.
[0057] When the rotor disc 27 rotates around its axis Ar, centrifugal force acts on the rotor blades 50 attached to the rotor disc 27. As a result, when the rotor disc 27 is rotating, the rotor blades 50 are positioned slightly radially outward (Dro) than when the rotor disc 27 is not rotating. Therefore, as the rotor disc 27 repeatedly rotates and stops, the blade root spring 90 repeatedly compresses and extends radially (Dr). When the blade root spring 90 is extended radially (Dr), the contact pressure between the blade root spring 90 and the base surface 65b of the blade root 65 decreases. At the same time, the contact pressure between the blade root spring 90 and the base surface 42b of the blade groove also decreases. Therefore, when the contact pressure between the wing root spring 90 and the root surface 65b is small, and the contact pressure between the wing root spring 90 and the bottom surface 42b of the wing groove is also small, the wing root spring 90 moves in the insertion direction Di within the wing groove 42, and there is a risk that a part of the wing root spring 90 may enter the passage groove 36. If a part of the wing root spring 90 enters the passage groove 36, the elastic force that the wing root spring 90 exerts on the rotor blade 50 will be reduced to the desired elastic force.
[0058] In this embodiment, since the bottom surface 81b of the lid is located radially inward (Dri) from the root surface 65b, a part of the lid member 80 faces a part of the wing root spring 90 in the insertion direction (Di). Therefore, in this embodiment, the movement of the wing root spring 90 in the insertion direction (Di) is restricted by the lid member 80, preventing a part of the wing root spring 90 from entering the passage groove 36.
[0059] The lid member 80 fitted into the passage groove 36 may become stuck to the passage groove 36. In this case, it becomes extremely difficult to remove the lid member 80 from the passage groove 36. In this embodiment, the lid member 80 has a tool engagement surface 82p, so as shown in Figure 8, by positioning a part of the tool 95 opposite this tool engagement surface 82p and moving the tool 95 to the second axis side Da2, the lid member 80 can be easily removed from the passage groove 36.
[0060] "Modification" In the above embodiments, the tool engagement surface 82p of the lid member 80 is a part of the inner circumferential surface of the tool hole 82. However, as shown in Figure 11, the tool engagement surface 82sp of the lid member 80 may be a part of the flank surface of the tool female screw hole 82s. This tool female screw hole 82s is a female screw hole that is recessed in the insertion direction Di toward the upstream side Dau (first side Da1) of the lid body 81 from the rear end surface (second side end surface) 81r. The tool engagement surface 82sp is a surface that extends in a direction having a directional component of a virtual plane VP that is facing the upstream side Dau (first side Da1) of the axial line and extending in a direction perpendicular to the insertion direction Di. The tool 95s has a male screw that can be screwed into the tool female screw hole 82s. When removing the lid member 80 from the passage groove 36, the male screw of the tool 95s is screwed into the female screw hole 82s of the tool in the lid member 80, and together with the tool 95s, the lid member 80 is moved to the second axis side Da2.
[0061] An example of the disk unit 25 in the above embodiment is the final stage disk unit 25f. However, the disk unit 25 may also be a disk unit 25 located in the Dau on the upstream side of the axis from the final stage disk unit 25f.
[0062] In the above embodiment, a small diameter portion 34 is provided on the downstream side Dad of the axis, which is the second side Da2 of the axis, relative to the large diameter portion 41. In this relationship, in the above embodiment, the cover member 80 and the seal plate 72 are arranged on the downstream side Dad of the axis, which is the second side Da2 of the axis, relative to the rotor blade 50. However, the second side Da2 of the axis may also be the upstream side Dau of the axis. That is, a small diameter portion 34 may be provided on the upstream side Dau of the axis, which is the second side Da2 of the axis, relative to the large diameter portion 41, and the cover member 80 and the seal plate 72 may be arranged on the upstream side Dau of the axis, which is the second side Da2 of the axis, relative to the rotor blade 50.
[0063] In the above embodiment, the fitting portion 83 of the first lid member 80A protrudes radially outward (Dro) from the plate-facing surface 84 of the lid body 81 of the first lid member 80A. However, if the fitting portion 83 of the first lid member 80A is provided on the lid body 81 of the first lid member 80A so that it can fit into the recess 74 of the seal plate 72, the lid body 81 of the first lid member 80A does not need to have a plate-facing surface 84.
[0064] This disclosure is not limited to the embodiments described above. Various additions, modifications, substitutions, partial deletions, etc., are possible without departing from the conceptual idea and spirit of the present invention derived from the claims and their equivalents.
[0065] "Note" In the above embodiments, the turbine rotor 23 is understood, for example, as follows.
[0066] (1) The turbine rotor 23 in the first embodiment comprises a rotor disk 27 centered on the axis Ar, a plurality of rotor blades 50 attached to the rotor disk 27 and arranged in the circumferential direction Dc with respect to the axis Ar, a cover member 80 provided for each of the plurality of rotor blades 50 and attached to the rotor disk 27, and a plurality of seal plates 72. Each of the plurality of rotor blades 50 has an airfoil shape with a cross section perpendicular to the radial direction Dr with respect to the axis Ar, and includes a blade body 51 extending in the radial direction Dr, a platform 52 provided at the end of the blade body 51 on the radially inner Dr, of the radially outer Dr and radially inner Dr, a shank 61 provided on the radially inner Dr of the platform 52 and extending in an insertion direction Di having a component of the axial direction Da in which the axis Ar extends within a virtual plane parallel to the axis Ar, a blade root 65 provided on the radially inner Dr of the shank 61 and extending in the insertion direction Di, and a blade cooling air passage 69 formed in a continuous manner within the blade root 65, the shank 61, the platform 52, and the blade body 51. The shank 61 has a second end face 63 facing the second side of the axis Da, which is one of two sides facing each other in the axial direction Da, the first side Da1 and the second side Da2. The blade root 65 has a second end face 67 facing the second side Da2 of the axis and connected to the second end face 63 of the shank 61, and a base surface 65b facing the radially inward direction Dri. The blade cooling air passage 69 opens at the base surface 65b of the blade root 65 and the blade surface of the blade body 51. The rotor disk 27 has a cylindrical small-diameter portion 34 centered on the axis Ar, and a large-diameter portion 41 that is cylindrical centered on the axis Ar and has an outer diameter larger than the outer diameter of the small-diameter portion 34. The small-diameter portion 34 is connected to the second side Da2 of the axis of the large-diameter portion 41. The small-diameter portion 34 has a passage groove 36 for each of the plurality of rotor blades 50. The passage groove 36 is recessed radially inward Dri from the outer circumferential surface of the small-diameter portion 34, with its radially outward edge Do forming an opening 36o, and extends toward the large-diameter portion 41 in the insertion direction Di. The large-diameter portion 41 has a blade groove 42 for each of the plurality of rotor blades 50.The blade groove 42 is recessed from the radially outer Dr to the radially inner Dr of the large diameter portion 41 so that the blade root 65 can be inserted, extends in the insertion direction Di and penetrates the large diameter portion 41. The blade groove 42 has a blade groove bottom surface 42b that faces radially outward Dr and is separated from the root bottom surface 65b of the blade root 65 by a distance in the radial direction Dr. The blade groove bottom surface 42b is connected to the passage groove bottom surface 36b, which is the bottom surface of the passage groove 36. Each of the plurality of seal plates 72 has a plate body 73 that faces the second side end surface 63 of the shank 61 of the plurality of rotor blades 50 and extends in the circumferential direction Dc, and has a recess 74 that closes the portion of the second side Da2 of the axis between the shanks 61 of each of the plurality of rotor blades 50. The plate body 73 has an outer peripheral edge 73o that faces radially outward Dr and extends in the circumferential direction Dc, and an inner peripheral edge 73i that faces radially inward Dri and extends in the circumferential direction Dc. The recess 74 is recessed from the inner peripheral edge 73i of the plate body 73 toward radially outward Dr. Each of the plurality of rotor blades 50 has a cover member 80 that closes the opening 36o of the passage groove 36. The cover body 81 has a cover bottom surface 81b that faces radially inward Dr. The position of the cover bottom surface 81b in the radial direction Dr is at a position that is spaced radially outward Dr relative to the passage groove bottom surface 36b. In the passage groove 36, the portion between the cover bottom surface 81b and the passage groove bottom surface 36b forms a passage through which cooling air can flow and which connects to the blade groove 42 of the large diameter portion 41. Of the lid members 80 for each of the plurality of rotor blades 50, at least one lid member, the first lid member 80A, is provided on the lid body 81 and has a fitting portion 83 that fits into the recess 74 of the seal plate 72.
[0067] In this embodiment, the seal plate 72 has a recess 74 that is recessed radially outward from the inner peripheral edge 73i of the plate body 73 toward Dr. Furthermore, the first lid member 80A in this embodiment has a fitting portion 83 that fits into the recess 74 of the seal plate 72. Therefore, in this embodiment, the movement of the seal plate 72 in the circumferential direction Dc can be restricted. Moreover, in this embodiment, there is no need to form a groove in the lid member 80 that is recessed radially inward toward Dr., so even when the lid member 80 is miniaturized, the movement of the seal plate 72 in the circumferential direction Dc can be restricted as described above.
[0068] Here, in order to explain other effects of this embodiment, a comparative example will be described. In this comparative example, the seal plate 72C has a projection 74C that protrudes radially inward Dri from the inner peripheral edge 73i of the plate body 73C. In this relationship, the lid member has a groove that is recessed toward radially inward Dri so that the projection 74C of the seal plate 72C can fit into it. When manufacturing this seal plate 72C, first a base plate 75C is prepared. The thickness of this base plate 75C is the same as the thickness of the seal plate 72C in the comparative example. The circumferential length Dc of this base plate 75C is the same as the circumferential length Dc of the seal plate 72C in the comparative example. The radial length Dr LC of this base plate 75C is the length obtained by adding the radial length Dr L of the projection 74C to the radial length Dr L of the plate body 73 in the comparative example. Then, the portion 76C of the radially inward Dri of this base plate 75C, excluding the portion that will become the projection 74C, is removed to complete the seal plate 72C.
[0069] In manufacturing the seal plate 72 in this embodiment, first, a base plate 75 is prepared. The thickness of this base plate 75 is the same as the thickness of the seal plate 72 in this embodiment. The length of the base plate 75 in the circumferential direction Dc is the same as the length of the seal plate 72 in the circumferential direction Dc in this embodiment. The length L of the base plate 75 in the radial direction Dr is the same as the length L of the plate body 73 in the radial direction Dr. Then, the portion 76 that will become the recess 74 is removed from the radially inner portion Dri of the base plate 75 to complete the seal plate 72.
[0070] In this embodiment, the radial length Dr L of the plate body 73 is the same as the radial length Dr L of the plate body 73 in the comparative example. Therefore, the radial length Dr L of the material plate 75 prepared in this embodiment is shorter than the radial length Dr LC of the material plate 75C prepared in the comparative example. Furthermore, when manufacturing the seal plate 72, in this embodiment, the amount of portion 76 removed from the material plate 75 is less than the amount of portion 76C removed from the material plate 75C in the comparative example. Therefore, in this embodiment, material costs can be reduced, and the amount of material waste can also be reduced.
[0071] As described above, in this embodiment, even when the lid member 80 is miniaturized, it is possible to restrict the movement of the sealing plate 72 in the circumferential direction Dc while keeping manufacturing costs down.
[0072] (2) The turbine rotor 23 in the second embodiment is such that, in the turbine rotor 23 in the first embodiment, of the cover members 80 for each of the plurality of rotor blades 50, the second cover member 80B, excluding the first cover member 80A, does not have the fitting portion 83 of the first cover member 80A, and has a plate facing surface 84 that faces radially outward Do and faces the inner peripheral edge 73i of the plate body 73.
[0073] In the fitting portion 83 of the first lid member 80A, the radial movement of the seal plate 72 in the radial direction Dr can be restricted by the surface facing radially outward Dr. However, if a part of the fitting portion 83 of the first lid member 80A is worn away during the process of repeatedly attaching and removing the first lid member 80A, the first lid member 80A cannot sufficiently restrict the radial movement of the seal plate 72 in the radial direction Dr. In this embodiment, even if a part of the fitting portion 83 of the first lid member 80A is worn away, the plate-facing surface 84 of the second lid member 80B can restrict the radial movement of the seal plate 72 in the radial direction Dr.
[0074] (3) The turbine rotor 23 in the third embodiment has a plurality of first cover members 80A and a plurality of second cover members 80B in the turbine rotor 23 in the second embodiment. The first cover members 80A and the second cover members 80B are arranged alternately in the circumferential direction Dc.
[0075] The length of the plate body 73 of the sealing plate 72 in the circumferential direction Dc is such that it can face two adjacent lid members 80 in the circumferential direction Dc, but cannot face three lid members 80 that are adjacent to each other in the circumferential direction Dc. Even in this case, in this embodiment, since the first lid member 80A and the second lid member 80B are arranged alternately in the circumferential direction Dc, the movement of the sealing plate 72 in the circumferential direction Dc and the radial direction Dr can be restricted.
[0076] (4) In the fourth embodiment, the turbine rotor 23 is such that, in any one embodiment of the first to third embodiments, the bottom surface of the cover 81b is located radially inward Dri than the root surface 65b.
[0077] When the rotor disc 27 rotates around its axis Ar, centrifugal force acts on the rotor blades 50 attached to the rotor disc 27. As a result, when the rotor disc 27 is rotating, the rotor blades 50 are positioned slightly radially outward (Dro) than when the rotor disc 27 is not rotating. Therefore, as the rotor disc 27 repeatedly rotates and stops, the blade root spring 90 repeatedly compresses and extends radially (Dr). When the blade root spring 90 is extended radially (Dr), the contact pressure between the blade root spring 90 and the base surface 65b of the blade root 65 decreases. At the same time, the contact pressure between the blade root spring 90 and the base surface 42b of the blade groove also decreases. Therefore, when the contact pressure between the wing root spring 90 and the root surface 65b is small, and the contact pressure between the wing root spring 90 and the bottom surface 42b of the wing groove is also small, the wing root spring 90 moves in the insertion direction Di within the wing groove 42, and there is a risk that a part of the wing root spring 90 may enter the passage groove 36. If a part of the wing root spring 90 enters the passage groove 36, the elastic force that the wing root spring 90 exerts on the rotor blade 50 will be reduced to the desired elastic force.
[0078] In this embodiment, since the bottom surface 81b of the lid is located radially inward (Dri) from the root surface 65b, a part of the lid member 80 faces a part of the wing root spring 90 in the insertion direction (Di). Therefore, in this embodiment, the movement of the wing root spring 90 in the insertion direction (Di) is restricted by the lid member 80, preventing a part of the wing root spring 90 from entering the passage groove 36.
[0079] (5) The turbine rotor 23 in the fifth embodiment is the turbine rotor 23 in any one of the first to fourth embodiments, wherein the cover body 81 has externally accessible tool engagement surfaces 82p, 82sp that extend in a direction that faces the first axis Da1 and includes a component perpendicular to the insertion direction Di.
[0080] The lid member 80 fitted into the passage groove 36 may become stuck to the passage groove 36. In this case, it becomes extremely difficult to remove the lid member 80 from the passage groove 36. In this embodiment, the lid member 80 has a tool engagement surface 82p, so by positioning a part of the tool 95 opposite this tool engagement surface 82p and moving the tool 95 to the second axis side Da2, the lid member 80 can be easily removed from the passage groove 36.
[0081] (6) The turbine rotor 23 in the sixth embodiment is the same as the turbine rotor 23 in the fifth embodiment, wherein the cover body 81 has a tool hole 82 that is recessed from the radially outer Dr to the radially inner Dr. The tool engagement surface 82p is formed of a part of the inner circumferential surface of the tool hole 82.
[0082] (7) The turbine rotor 23 in the seventh embodiment is the same as the turbine rotor 23 in the fifth embodiment, wherein the cover body 81 has a tool female screw hole 82s recessed in the insertion direction Di from the second axis side Da2 toward the first axis side Da1. The tool engagement surface 82sp is formed of a part of the flank surface of the tool female screw hole 82s.
[0083] (8) The turbine rotor 23 in the eighth embodiment is the turbine rotor 23 described in any one of the first to seventh embodiments, and includes a lid retaining member 85 that contacts the surface of the lid member 80 facing the second axis Da2 and restricts the movement of the lid member 80 toward the second axis Da2 relative to the rotor disk 27. The small diameter portion 34 has a lid retaining groove 38 that is recessed from the radially outer Doro toward the radially inner Dri, into which the lid retaining member 85 fits.
[0084] In this embodiment, the movement of the lid member 80 toward the second axis Da2 can be restricted.
[0085] The gas turbine in the above embodiments can be understood, for example, as follows: (9) The gas turbine in the ninth embodiment comprises a turbine rotor 23 in any one of the first to eighth embodiments, and a turbine casing 21 covering the outer circumference of the turbine rotor 23.
[0086] According to one aspect of this disclosure, it is possible to restrict the circumferential movement of the seal plate while keeping manufacturing costs down.
[0087] 1: Gas turbine casing 2: Intermediate casing 3: Gas turbine rotor 10: Compressor 11: Compressor casing 12: Stationary blade row 13: Compressor rotor 13b: Rotor blade row 13r: Rotor shaft 15: Combustor 20: Turbine 21: Turbine casing 22: Stationary blade row 23: Turbine rotor 23b: Rotor blade row 23r: Rotor shaft 25: Disk unit 25f: Final stage disk unit 26: Spindle bolt 27: Rotor disk 27f: (Final stage) rotor disk 28: Rear shaft section 29: Main cooling air passage 31: First small diameter section 32: First radial passage 33: Axial passage 34: Second small diameter section (or simply small diameter section) 35: Second radial passage (or simply radial passage) 36: Passage groove 36b: Bottom surface of passage groove 36o: Opening 37: Seal plate groove 38: Cover retaining groove 39: Insertion direction passage 41: Large diameter section 41o: Outer surface 42: Wing groove 42b: Wing groove bottom surface 42f: First wide section 43: Insertion direction passage 50: Movable blade 51: Wing body 52: Platform 53: Gas pass surface 54: Anti-gas pass surface 55: Front end surface 56: Rear end surface 57: Side surface 58: Front seal plate groove 59: Rear seal plate groove 61: Shank 62: Front end surface 63: Rear end surface (or second side end surface) 64: Side surface 65: Wing root 65b: Root bottom surface 65f: First wide section 66: Front end surface 67: Rear end surface (or second side end surface) 68: Side surface 69: Wing cooling air passage 70: Front seal plate 71: Front seal plate retaining member 72, 72C: Rear seal plate (or simply seal plate) 73: Plate body 73i: Inner edge 73o: Outer edge 74: Recess 74C: Protrusion 80: Lid member 80A: First lid member 80B: Second lid member 81: Lid body 81b: Lid bottom surface 81f: Front end surface 81r: Rear end surface (or second side end surface) 82: Tool hole 82s: Tool female screw hole 82p, 82sp: Tool engagement surface 83: Fitting part 84: Plate opposing surface 85: Lid retaining member 86: First retaining member 86s: Female screw 87: Second retaining member 87s: Female screw 88: Spacing changing member 90: Wing root spring 95, 95s: Tool A: Air Ac: Cooling air F: Fuel G: Combustion gas Ar: Axis Da: Axial direction Dau: Upstream side of axis Dad: Downstream side of axis Da1: First side of axis Da2: Second side of axis Dc: Circumferential direction Dr: Radial direction Dri: Inner radial direction Dro: Outer radial direction Di: Insertion direction
Claims
1. A rotor disk centered on an axis; a plurality of rotor blades attached to the rotor disk, arranged in a circumferential direction with respect to the axis; a cover member provided for each of the plurality of rotor blades and attached to the rotor disk; a plurality of seal plates, wherein each of the plurality of rotor blades has an airfoil-shaped cross section perpendicular to the radial direction with respect to the axis and extends in the radial direction; a platform provided at the end of the airfoil on the radially inner side of the airfoil, between the radially outer and radially inner sides in the radial direction; a shank provided on the radially inner side of the platform and extending in the insertion direction having an axial component in which the axis extends in a virtual plane parallel to the axis; a blade root provided on the radially inner side of the shank and extending in the insertion direction; and a blade cooling air passage formed in connection with the blade root, the shank, the platform, and the airfoil body. The shank has a second end face facing the second axis side, which is one of two sides opposite to the first axis side in the axial direction; the blade root has a second end face facing the second axis side and connected to the second end face of the shank, and a base surface facing radially inward; the blade cooling air passage opens at the base surface of the blade root and the blade surface of the blade body; the rotor disc has a cylindrical small-diameter portion centered on the axis and a large-diameter portion that is cylindrical centered on the axis and has an outer diameter larger than the outer diameter of the small-diameter portion; the small-diameter portion is connected to the second axis side of the large-diameter portion; the small-diameter portion has a passage groove for each of the plurality of rotor blades; the passage groove is recessed radially inward from the outer circumferential surface of the small-diameter portion, with its radially outer edge forming an opening, and extends toward the large-diameter portion in the insertion direction; The large-diameter portion has a blade groove for each of the plurality of rotor blades, the blade groove is recessed from the radially outer to the radially inward portion of the large-diameter portion so that the blade root can be inserted, extends in the insertion direction and penetrates the large-diameter portion, the blade groove has a blade groove bottom surface that faces radially outward and is spaced radially apart from the root bottom surface of the blade root, the blade groove bottom surface is connected to the passage groove bottom surface which is the bottom surface of the passage groove,Each of the plurality of sealing plates has a plate body that faces the second side end face of the shank of the plurality of rotor blades and extends in the circumferential direction, closing the portion on the second axis side between the shanks of each of the plurality of rotor blades, and a recess, the plate body has an outer peripheral edge that faces radially outward and extends in the circumferential direction, and an inner peripheral edge that faces radially inward and extends in the circumferential direction, the recess is recessed radially outward from the inner peripheral edge of the plate body, each of the plurality of rotor blades has a lid body that closes the opening of the passage groove, the lid body has a lid bottom surface that faces radially inward, the radial position of the lid bottom surface is at a position that is radially outward with respect to the bottom surface of the passage groove, and in the passage groove, the portion between the lid bottom surface and the bottom surface of the passage groove forms a passage through which cooling air can flow and which is connected to the blade groove of the large diameter portion. A turbine rotor in which at least one of the cover members for each of the plurality of rotor blades, the first cover member, is provided on the cover body and has a fitting portion that fits into the recess of the seal plate.
2. A turbine rotor according to claim 1, wherein, of the cover members for each of the plurality of rotor blades, the second cover member, excluding the first cover member, does not have a fitting portion in the first cover member, and has a plate-facing surface that faces radially outward and faces the inner peripheral edge of the plate body.
3. A turbine rotor according to claim 2, wherein the turbine rotor has a plurality of first cover members and a plurality of second cover members, and the first cover members and the second cover members are arranged alternately in the circumferential direction.
4. A turbine rotor according to claim 1, wherein the bottom surface of the cover is located radially inward from the root bottom surface.
5. A turbine rotor according to claim 1, wherein the cover body has an externally accessible tool engagement surface that extends in a direction that faces the first axis and includes a component perpendicular to the insertion direction.
6. A turbine rotor according to claim 5, wherein the cover body has a tool hole recessed from the radially outer side toward the radially inner side, and the tool engagement surface is formed of a part of the inner circumferential surface of the tool hole.
7. A turbine rotor according to claim 5, wherein the cover body has a female screw hole for tools that is recessed in the insertion direction from the second side of the axis toward the first side of the axis, and the tool engagement surface is formed of a part of the flank surface of the female screw hole for tools.
8. A turbine rotor according to claim 1, comprising a lid retaining member that contacts the surface of the lid member facing the second axis side and restricts the movement of the lid member toward the second axis side relative to the rotor disk, wherein the small diameter portion has a lid retaining groove that is recessed from the radially outer side toward the radially inner side into which the lid retaining member fits.
9. A gas turbine comprising: a turbine rotor according to any one of claims 1 to 8; and a turbine casing covering the outer circumference of the turbine rotor.