Turbines and heat shields

Abstract

To provide a turbine which can easily prevent damage and can improve sealing characteristics between heat insulation pieces.SOLUTION: A turbine in an embodiment has a heat insulation member with a plurality of heat insulation pieces arranged in a rotation direction of a turbine rotor in a portion of an external peripheral surface of the turbine rotor that lies opposite a stationary blade. Each of the plurality of heat insulation pieces includes a front end face located on a front side in the rotation direction, and a rear end face located on a rear side in the rotation direction, with a protrusion provided on either of the front end face and the rear end face and a recess provided in the other of the front end face and the rear end face. The protrusion is formed integrally with the heat insulation piece. By the protrusion being accommodated in the recess between the plurality of heat insulation pieces, a clearance between the plurality of heat insulation pieces is sealed.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] Embodiments of the present invention relate to turbines and heat insulation devices.

Background Art

[0002] In a power generation plant equipped with a turbine such as a gas turbine, in order to improve power generation efficiency, the temperature of the working medium supplied to the inlet of the turbine is high. Therefore, in the turbine, a heat insulation device is provided to protect members such as the turbine rotor and moving blades from the high-temperature working medium and maintain their strength.

[0003] The heat insulation device is, for example, a heat insulation member provided on a portion of the outer peripheral surface of the turbine rotor facing the stator blades. The heat insulation member is configured, for example, by arranging a plurality of heat insulation pieces in the rotational direction of the turbine rotor. And it has been proposed to introduce a cooling fluid into the space intervening between the heat insulation member and the turbine rotor.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Summary of the Invention

Problems to be Solved by the Invention

[0005] [A] Configuration of the Turbine Paragraph Figure 8A shows the main part of the turbine stage in a turbine relating to the related technology. In Figure 8A, a partial cross-section of the vertical plane (xz plane) is schematically shown, where the vertical direction is the vertical direction z, the horizontal direction is the first horizontal direction x, and the direction perpendicular to the plane of the paper is the second horizontal direction y. In Figure 8A, the flow direction of the working fluid M is indicated by a thick arrow, with the left side being the upstream side Us and the right side being the downstream side Ds.

[0006] [A-1] Turbine rotor 43 In the turbine 4, the turbine rotor 43 is housed in a casing 41 and is configured to rotate in the rotational direction R by the flow of a working fluid M in the axial direction along the rotation axis AX. The turbine rotor 43 has a rotor body 431 on which rotor discs 432 are provided. The rotor body 431 extends along the rotation axis AX. Multiple rotor discs 432 are provided so as to protrude convexly from the outer circumferential surface of the rotor body 431. The multiple rotor discs 432 are spaced apart in the axial direction (x) along the rotation axis AX. Rotary blades 46 are provided on the outer circumferential surface of the rotor discs 432.

[0007] [A-2] Moving blade 46 The rotor blades 46 have a mounting portion 461 on the inner side (lower side in Figure 8A) in the radial direction of the turbine rotor 43. The mounting portion 461 is fitted onto the outer circumferential surface of the rotor disk 432.

[0008] [A-3] Stable Wing 45 The stationary vanes 45 are installed on the inner circumferential surface of the casing 41. The stationary vanes 45 are provided with a diaphragm inner ring 451 on the radial side of the turbine rotor 43. Seal fins 451f are provided on the inner circumferential surface of the diaphragm inner ring 451.

[0009] [A-4] Heat-shielding material 50 Furthermore, a heat shield member 50 is provided as a heat shielding device on the outer circumferential surface of the turbine rotor 43 that faces the stationary blades 45. Here, the heat shield member 50 is supported on the outer circumferential surface of the rotor body portion 431 that constitutes the turbine rotor 43, on the portion that faces the inner circumferential surface of the diaphragm inner ring 451. The heat shield member 50 blocks the main flow path through which the working fluid flows inside the casing 41 from the turbine rotor 43, and is provided to protect the turbine rotor 43 from the heat of the working fluid.

[0010] The heat shield member 50 comprises a heat shield plate 51 and legs 52, and the heat shield plate 51 and legs 52 are sequentially provided as you move from the outside to the inside (from the top to the bottom in Figure 8A) in the radial direction of the turbine rotor 43.

[0011] In the heat shield member 50, the heat shield plate 51 includes a portion that extends along the rotation axis AX of the turbine rotor 43. The heat shield plate 51 is installed such that there is a gap between the outer surface of the heat shield plate 51 and the inner surface of the diaphragm inner ring 451, and a space SP is interposed between the inner surface of the heat shield plate 51 and the outer surface of the rotor body portion 431.

[0012] In the heat shield member 50, the leg portion 52 extends radially across the turbine rotor 43. A groove TR is formed on the outer circumferential surface of the rotor body portion 431 facing the inner circumferential surface of the diaphragm inner ring 451, and the radially inner portion of the leg portion 52 engages with the groove TR. The leg portion 52 is configured to engage with the groove TR by being inserted, for example, in the axial direction. Alternatively, the leg portion 52 may be configured to engage with the groove TR by being inserted, for example, in the rotational direction R.

[0013] Here, the leg portion 52 is configured to divide the space SP interposed between the inner circumferential surface of the heat shield plate 51 and the outer circumferential surface of the rotor body portion 431 into an upstream space SU located on the upstream side Us in the axial direction and a downstream space SD located on the downstream side Ds in the axial direction.

[0014] Cooling fluid CF is introduced into the upstream space SU. Here, for example, cooling fluid CF is introduced from an inlet formed in the turbine rotor 43. In addition, the cooling fluid CF introduced into the upstream space SU is introduced into the downstream space SD via the gap interposed between the leg portion 52 and the engaged groove TR. The cooling fluid CF introduced into the upstream space SU and the downstream space SD is blown out into the main flow path through the space between the heat shield plate 51 and the planted portion 461, into which the working fluid flows. This prevents the working fluid from flowing into the upstream space SU and the downstream space SD.

[0015] Figure 8B shows a portion of a turbine related to the relevant technology in which a heat shield member 50 is provided. In Figure 8B, the cross-section of the heat shield member 50 is schematically shown in the x1-x1 portion shown in Figure 8A, which is the vertical plane (yz plane) where the rotation axis AX of the turbine rotor 43 is perpendicular.

[0016] As shown in Figure 8B, the heat shield member 50 includes a plurality of heat shield pieces 500. The plurality of heat shield pieces 500 are components that divide the heat shield member 50 in the rotation direction R of the turbine rotor 43. The heat shield pieces 500 have an arc shape along the rotation direction R, and the heat shield member 50 is configured in a ring shape by arranging the plurality of heat shield pieces 500 so that they are aligned in the rotation direction R.

[0017] The heat shield piece 500 includes a heat shield plate piece 510 and a leg piece 520. Multiple heat shield plate pieces 510 of the heat shield piece 500 are arranged in the rotational direction R of the turbine rotor 43 to form the heat shield plate 51 of the heat shield member 50. Multiple leg pieces 520 of the heat shield piece 500 are arranged in the rotational direction R of the turbine rotor 43 to form the leg portion 52 of the heat shield member 50.

[0018] Each of the multiple heat shield pieces 500 includes a front end face SF located on the front side Fw in the rotational direction R, and a rear end face SB located on the rear side Bw in the rotational direction R, as shown in Figure 8B.

[0019] In the heat insulation piece 500 shown in FIG. 8A, the rear end face SB is illustrated. As shown in FIG. 8A, recesses R51 and R52 are formed in the rear end face SB of the heat insulation piece 500. A seal pin 61 is accommodated inside the recess R51, and a seal pin 62 is accommodated inside the recess R52. The seal pins 61 and 62 are installed to seal between a plurality of heat insulation pieces 500 arranged in the rotational direction R.

[0020] FIG. 8C is a view showing an enlarged part of a heat insulation member 50 in a turbine according to the related art. In FIG. 8C, among vertical planes (yz planes) orthogonal to the rotation axis AX of the turbine rotor 43 in the heat insulation member 50, a part between a pair of heat insulation pieces 500 arranged adjacent to each other in the rotational direction R is shown enlarged. Here, a part (portion X in FIG. 8B) between a pair of heat insulation plate pieces 510 constituting the heat insulation plate 51 is shown enlarged. In FIG. 8C, the horizontal direction is substantially the rotational direction R, the left side is the front side Fw of the rotational direction R, and the right side is the rear side Bw of the rotational direction R. In FIG. 8C, the vertical direction substantially corresponds to the radial direction.

[0021] As shown in FIG. 8C, the seal pin 61 shown in FIG. 8A is interposed between a pair of heat insulation plate pieces 510. The seal pin 61 is, for example, a cylindrical rod-shaped body. Here, in one of the pair of heat insulation plate pieces 510, a recess R510 is formed in the rear end face SB of the heat insulation plate piece 510 located on the front side Fw of the rotational direction R, and the seal pin 61 is accommodated inside the recess R510. Although not shown, the other seal pin 62 shown in FIG. 8A has the same shape as the seal pin 61, and the other seal pin 62 is also accommodated in a recess R520 in the same manner as the seal pin 61.

[0022] [B] Problem During the operation of the turbine, a large radial centrifugal force is applied to each of the heat shield pieces 500 as the turbine rotor 43 rotates. Therefore, the gap between the front end surface SF of one heat shield piece 500 and the rear end surface SB of another heat shield piece 500 located on the front side Fw of the one heat shield piece 500 widens. If this gap becomes wider than expected due to a failure or the like, in the related art described above, the seal pin 61 may fall out of the recess R51, and the seal pin 62 may fall out of the recess R52. As a result, damage or the like may occur.

[0023] Also, due to the centrifugal force applied during the operation of the turbine, the seal pin 61 moves radially outward inside the recess R51 as shown in FIG. 8C. As a result, a communication passage LC that communicates between the upstream space SU and the downstream space SD may be formed inside the recess R51. Along with this, the flow rate of the cooling fluid CF flowing from the upstream space SU to the downstream space SD may increase. That is, the sealing characteristics between the heat shield pieces 500 may deteriorate. As a result, the performance of the turbine may deteriorate.

[0024] Therefore, the problem to be solved by the present invention is to provide a turbine and a heat shielding device that can easily prevent damage, improve the sealing characteristics between the heat shield pieces, and easily improve the performance of the turbine.

Means for Solving the Problem

[0025] The turbine according to the embodiment includes a casing, a turbine rotor housed in the casing and rotated by the flow of a working medium in the axial direction along the rotation axis, and a turbine stage including stationary blades installed inside the casing and moving blades installed on the outer peripheral surface of the turbine rotor. A plurality of turbine stages are provided in the axial direction. The turbine according to the embodiment has a plurality of heat shield pieces arranged in the rotation direction of the turbine rotor at a portion of the outer peripheral surface of the turbine rotor that faces the stationary blades. It is composed ofThe device has a heat-shielding member. Each of the multiple heat-shielding pieces includes a front end face located on the front side in the direction of rotation and a rear end face located on the rear side in the direction of rotation. One of the front and rear end faces is provided with a protrusion, and the other of the front and rear end faces is provided with a recess. The protrusion is formed integrally with the heat-shielding piece. Between each of the multiple heat-shielding pieces, the protrusion is accommodated in the recess, thereby sealing the space between each of the multiple heat-shielding pieces. The heat shield member has legs whose inner portion engages with an engagement groove formed on the outer circumferential surface of the turbine rotor, and a heat shield plate located on the outer portion of the legs. The legs are configured to partition an upstream space located upstream in the axial direction and a downstream space located downstream. The protrusions between each of the multiple heat shield pieces are accommodated in recesses, thereby sealing the space between the upstream and downstream spaces and preventing leakage of cooling fluid from the upstream space to the downstream space. [Brief explanation of the drawing]

[0026] [Figure 1] Figure 1 is a diagram showing the main parts of a turbine according to the first embodiment as an example. [Figure 2] Figure 2 shows the main part of the turbine stage in the turbine according to the first embodiment. [Figure 3A] Figure 3A is a schematic diagram showing the rear end face SB of the heat shield piece 500 that constitutes the heat shield member 50 of the first embodiment. [Figure 3B] Figure 3B is a schematic diagram showing the front end face SF of the heat shield piece 500 that constitutes the heat shield member 50 of the first embodiment. [Figure 3C] Figure 3C shows an enlarged view of the space between a pair of heat-shielding pieces 500 that are adjacent to each other in the rotational direction R in the heat-shielding member 50 of the first embodiment. [Figure 4A] Figure 4A is a schematic diagram showing the rear end face SB of a heat shield piece 500 that constitutes the heat shield member 50 of the second embodiment. [Figure 4B] Figure 4B is a schematic diagram showing the front end face SF of the heat shield piece 500 that constitutes the heat shield member 50 of the second embodiment. [Figure 5A] Figure 5A is a schematic diagram showing the rear end face SB of a heat shield piece 500 that constitutes the heat shield member 50 of the third embodiment. [Figure 5B] Figure 5B is a schematic diagram showing the front end face SF of the heat shield piece 500 that constitutes the heat shield member 50 of the third embodiment. [Figure 6] Figure 6 shows an enlarged view of the space between a pair of heat-shielding pieces 500 that are adjacent to each other in the rotational direction R in the heat-shielding member 50 of the fourth embodiment. [Figure 7] Figure 7 shows an enlarged view of the space between a pair of heat-shielding pieces 500 that are adjacent to each other in the rotational direction R in the heat-shielding member 50 of the fifth embodiment. [Figure 8A] Figure 8A shows the main part of the turbine stage in a turbine related to the relevant technology. [Figure 8B] Figure 8B shows the portion of a turbine related to the relevant technology in which the heat shielding member 50 is provided. [Figure 8C] Figure 8C is a diagram showing an enlarged view of a part of the heat shield member 50 in a turbine related to the relevant technology. [Modes for carrying out the invention]

[0027] <First Embodiment>

[0028] [A] Turbine configuration Figure 1 is a diagram showing the main parts of a turbine according to the first embodiment as an example.

[0029] Figure 1 shows a partial cross-section of a vertical plane (xz plane), where the vertical direction is the vertical direction z, the horizontal direction is the first horizontal direction x, and the direction perpendicular to the plane of the paper is the second horizontal direction y. Also in Figure 1, the flow of the working fluid through turbine 4 is indicated by a thick arrow, with the left side being the upstream side Us and the right side being the downstream side Ds.

[0030] As shown in Figure 1, the turbine 4 comprises a casing 41 and a turbine rotor 43. The turbine 4 is, for example, a multi-stage turbine with multiple turbine stages 47. The turbine 4 is, for example, a gas turbine.

[0031] We will now explain each component of the turbine 4 in order.

[0032] The casing 41 is, for example, a double structure having an inner casing 41a and an outer casing 41b, where the outer casing 41b houses the inner casing 41a. In the casing 41, stator blades 45 are installed on the inner circumferential surface of the inner casing 41a. Multiple stator blades 45 are arranged in the rotation direction R (circumferential direction) of the turbine rotor 43, and the multiple stator blades 45 constitute a stator blade row. The stator blade row consists of multiple stages, and the multiple stages of stator blade rows are arranged in the axial direction (first horizontal direction x) along the rotation axis AX of the turbine rotor 43.

[0033] The turbine rotor 43 is a cylindrical rod-shaped body with a rotation axis AX extending in a first horizontal direction x. The turbine rotor 43 is housed inside a casing 41 and is supported to rotate as a working fluid flows axially along the rotation axis AX. The turbine rotor 43 has rotor blades 46 installed on its outer circumferential surface. Multiple rotor blades 46 are arranged in the rotation direction R of the turbine rotor 43, and the multiple rotor blades 46 constitute a rotor blade row. The rotor blade row, like the stator blade row, is in multiple stages, and the multiple stages of rotor blade rows are arranged along the axial direction (x) along the rotation axis AX of the turbine rotor 43. In other words, the turbine stage 47, which is composed of the stator blade row and the rotor blade row, is in multiple stages, and the multiple stages of turbine stage 47 are arranged axially along the rotation axis AX.

[0034] The turbine 4 is equipped with, for example, a gas supply pipe 411, an inlet sleeve 421, and a nozzle box 422 to introduce combustion gas supplied as a working fluid from a combustor (not shown) into the casing 41. The gas supply pipe 411 is located outside the outer casing 41b. The inlet sleeve 421 is provided so as to penetrate the inner casing 41a and the outer casing 41b. The nozzle box 422 is located inside the inner casing 41a.

[0035] In turbine 4, the working fluid flows sequentially through the gas supply pipe 411, the inlet sleeve 421, and the nozzle box 422, and then flows axially (x) along the rotation axis AX of the turbine rotor 43. At this time, the working fluid expands and performs work in each of the multiple turbine stages 47 that are arranged axially (x) along the rotation axis AX. As a result, the turbine rotor 43 rotates in the rotational direction R. After passing through the final turbine stage 47, the working fluid is discharged to the outside of the casing 41 via the exhaust pipe 412.

[0036] [B] Turbine paragraph structure Figure 2 shows the main part of the turbine stage in the turbine according to the first embodiment.

[0037] Figure 2 schematically shows a partial cross-section of a vertical plane (xz plane), similar to Figure 8A. As shown in Figure 2, in the turbine according to this embodiment, a heat shield member 50 is provided as a heat shield device, similar to the case of the related technology described above (see Figure 8A). The heat shield member 50 comprises a heat shield plate 51 and leg portions 52. The heat shield member 50 is arranged such that a plurality of heat shield pieces 500 are aligned in the rotation direction R, similar to the case of the related technology described above (see Figure 8B). Each of the plurality of heat shield pieces 500 includes a front end face SF located on the front side Fw in the rotation direction R and a rear end face SB located on the rear side Bw in the rotation direction R (see Figure 8B). In the heat shield piece 500 shown in Figure 2, the rear end face SB is shown.

[0038] Figure 3A schematically shows the rear end face SB of a heat shield piece 500 that constitutes the heat shield member 50 of the first embodiment. Figure 3B schematically shows the front end face SF of a heat shield piece 500 that constitutes the heat shield member 50 of the first embodiment. Figure 3C shows an enlarged view of the space between a pair of heat shield pieces 500 that are adjacent to each other in the rotational direction R of the heat shield member 50 of the first embodiment. In Figure 3C, similar to Figure 8C, the portion between a pair of heat shield plate pieces 510 that constitute the heat shield plate 51 in the heat shield piece 500 (part X in Figure 8B) is shown in an enlarged view.

[0039] As shown in Figures 2, 3A, 3B, and 3C, the turbine according to this embodiment differs from the case of the related technology described above (see Figures 8A and 8C) in that a part of the heat shield piece 500 constituting the heat shield member 50 is different. Except for this point and related points, this embodiment is the same as the case of the related technology described above, so the explanation of overlapping parts will be omitted as appropriate.

[0040] As shown in Figures 2, 3A, 3B, and 3C, the heat shield piece 500 of this embodiment has a protrusion T50 on its rear end face SB and a recess R50 on its front end face SF. Here, the protrusion T50 is integrally formed with the heat shield piece 500.

[0041] Specifically, in this embodiment, the heat shield piece 500 includes a leg piece 520 that constitutes the leg portion 52 and a heat shield plate piece 510 that constitutes the heat shield plate 51, as shown in Figures 3A and 3B.

[0042] As shown in Figure 3A, the protrusion T50 is T-shaped and includes a first protrusion T51 and a second protrusion T52. In the protrusion T50, the first protrusion T51 is provided on the front end face SF of the heat shield piece 510. The first protrusion T51 extends axially along the rotation axis AX of the turbine rotor 43. In the protrusion T50, the second protrusion T52 is provided on the front end face SF of the leg piece 520. The second protrusion T52 extends radially of the turbine rotor 43, and the portion of the second protrusion T52 located radially outward is configured to connect to the first protrusion T51.

[0043] As shown in Figure 3B, the recess R50 is T-shaped and includes a first recess R51 and a second recess R52. In the recess R50, the first recess R51 is provided on the rear end face SB of the heat shield piece 510. The first recess R51 extends axially along the rotation axis AX of the turbine rotor 43, similar to the first protrusion T51. In the recess R50, the second recess R52 is provided on the rear end face SB of the leg piece 520. The second recess R52 extends radially along the turbine rotor 43, similar to the second protrusion T52, and the portion of the second recess R52 located radially outward is configured to connect to the first recess R51.

[0044] As shown in Figure 3C, the convex portion T50 is housed in a recess R50 between a pair of heat shield pieces 500 that are adjacent to each other in the rotational direction R. Specifically, the first convex portion T51 that constitutes the convex portion T50 is housed in the first recess R51 that constitutes the recess R50. Although not shown in the figure, similar to the relationship between the first convex portion T51 and the first recess R51, the second convex portion T52 that constitutes the convex portion T50 is housed in the second recess R52 that constitutes the recess R50. In other words, of the pair of heat shield pieces 500 that are adjacent to each other in the rotational direction R, the convex portion T50 that protrudes in the rotational direction R from the rear end face SB of one heat shield piece 500 (the first heat shield piece) is housed in a recess R50 that is recessed in the rotational direction R from the front end face SF of the other heat shield piece 500 (the second heat shield piece) located on the rear side Bw of the first heat shield piece 500.

[0045] In this embodiment, for example, the protrusion T50 and recess R50 are formed by machining the main body of the heat shield piece 500. Alternatively, a separate component for the protrusion T50 may be prepared and joined to the main body of the heat shield piece 500 by welding or other means.

[0046] [C] Summary As described above, in the turbine of this embodiment, the heat shielding member 50 installed as a heat shielding device has a convex portion T50 housed in a concave portion R50 between each of the multiple heat shielding pieces 500. As a result, the heat shielding member 50 of this embodiment seals the space between each of the multiple heat shielding pieces 500.

[0047] Unlike related technologies, this embodiment does not have seal pins 61 and 62 (see Figure 8A), and the protrusion T50 is integrally formed with the heat shield piece 500. Therefore, even if a large centrifugal force is applied to each of the multiple heat shield pieces 500 during the operation of the turbine 4, and the width of the gap between the multiple heat shield pieces 500 widens, in this embodiment, unlike the seal pins 61 and 62 (see Figure 8A) of related technologies, the protrusion T50 will not fall off. As a result, damage and other problems can be prevented in this embodiment.

[0048] Furthermore, in this embodiment, unlike the seal pins 61 and 62 of related technology (see Figure 8A), the protrusion T50 does not move inside the recess R51 even when centrifugal force is applied during turbine operation. Therefore, in this embodiment, even if a connecting passage exists inside the recess R51 that connects the upstream space SU and the downstream space SD, the cross-sectional area of ​​the connecting passage remains constant, so the flow rate of the cooling fluid CF from the upstream space SU to the downstream space SD does not fluctuate. In other words, in this embodiment, the sealing characteristics between the heat shield pieces 500 do not deteriorate even during turbine operation. In addition, in this embodiment, it is possible to suppress leakage of the cooling fluid CF from between the multiple heat shield pieces 500 into the main flow path through which the working fluid flows in the turbine. As a result, it is possible to prevent a decrease in turbine performance in this embodiment.

[0049] [D] Variation In the above embodiment, a case is described in which, in a pair of heat shield pieces 500 arranged adjacent to each other in the rotational direction, a protrusion T50 is provided on the rear end face SB of one heat shield piece 500 (first heat shield piece), and a recess R50 is provided on the front end face SF of the other heat shield piece 500 (second heat shield piece) located on the rear side Bw of the first heat shield piece 500, but the embodiment is not limited to this. A recess R50 may be provided on the rear end face SB of one heat shield piece 500, and a protrusion T50 may be provided on the front end face SF of the other heat shield piece 500. Each of the multiple heat shield pieces is provided with a protrusion on one of the rear end face SB and front end face SF facing each other in a pair of heat shield pieces 500 arranged adjacent to each other in the rotational direction, and a recess on the other end face.

[0050] <Second Embodiment> [A] Composition of heat shield piece 500 Figure 4A is a schematic diagram showing the rear end face SB of the heat shield piece 500 that constitutes the heat shield member 50 of the second embodiment. Figure 4B is a schematic diagram showing the front end face SF of the heat shield piece 500 that constitutes the heat shield member 50 of the second embodiment.

[0051] As shown in Figures 4A and 4B, in this embodiment, a part of the heat shield piece 500 differs from that of the first embodiment described above (see Figures 3A and 3B). Except for this point and related points, this embodiment is the same as that of the first embodiment described above, so the explanation of overlapping parts will be omitted as appropriate.

[0052] As shown in Figures 4A and 4B, the heat shield piece 500 of this embodiment has a protrusion T50 on its rear end face SB and a recess R50 on its front end face SF.

[0053] In the heat shield piece 500 of this embodiment, the protrusion T50 includes a first protrusion T51 and a second protrusion T52, as shown in Figure 4A. However, in this embodiment, unlike in the first embodiment, the first protrusion T51 has a first radial protrusion T511 and a first axial protrusion T512.

[0054] As shown in Figure 4A, the first radial protrusion T511 extends radially in the turbine rotor 43 of the heat shield piece 510. The first radial protrusion T511 is formed to be aligned with the second protrusion T52 in the radial direction. In contrast, the first axial protrusion T512 extends axially in the turbine rotor 43 of the heat shield piece 510. In other words, in the heat shield piece 500 of this embodiment, the protrusion T50 is formed in a cross shape.

[0055] In the heat shield piece 500 of this embodiment, the recess R50 includes a first recess R51 and a second recess R52, as shown in Figure 4B. However, in this embodiment, unlike in the first embodiment, the first recess R51 has a first radial recess R511 and a first axial recess R512.

[0056] As shown in Figure 4B, the first radial recess R511 extends radially in the heat shield piece 510 relative to the turbine rotor 43. The first radial recess R511 is formed to be aligned with the second recess R52 in the radial direction. In contrast, the first axial recess R512 extends axially in the heat shield piece 510 relative to the turbine rotor 43. In other words, in the heat shield piece 500 of this embodiment, the recess R50 is formed in a cross shape.

[0057] [B] Summary As described above, in the heat shield piece 500 of this embodiment, the first protrusion T51 constituting the protrusion T50 has a first radial protrusion T511 and a first axial protrusion T512. Furthermore, in the heat shield piece 500 of this embodiment, the first recess R51 constituting the recess R50 has a first radial recess R511 and a first axial recess R512. For this reason, in this embodiment, the shape of the gap interposed between the protrusion T50 and the recess R50 is more complex than in the first embodiment, so the cooling fluid CF passing through the gap interposed between the protrusion T50 and the recess R50 experiences increased pressure loss. As a result, in this embodiment, leakage of the cooling fluid CF from the upstream space SU to the downstream space SD can be suppressed more effectively than in the first embodiment.

[0058] <Third Embodiment> [A] Composition of heat shield piece 500 Figure 5A schematically shows the rear end face SB of the heat shield piece 500 that constitutes the heat shield member 50 of the third embodiment. Figure 5B schematically shows the front end face SF of the heat shield piece 500 that constitutes the heat shield member 50 of the third embodiment.

[0059] As shown in Figures 5A and 5B, in this embodiment, a part of the heat shield piece 500 differs from that of the second embodiment described above (see Figures 4A and 4B). Except for this point and related points, this embodiment is the same as that of the second embodiment described above, so the explanation of overlapping parts will be omitted as appropriate.

[0060] As shown in Figures 5A and 5B, the heat shield piece 500 of this embodiment has a protrusion T50 on its rear end face SB and a recess R50 on its front end face SF.

[0061] In the heat shield piece 500 of this embodiment, as shown in Figure 5A, it includes a first protrusion T51 and a second protrusion T52.

[0062] In the protrusion T50 of this embodiment, the first protrusion T51, as shown in Figure 5A, has a first radial protrusion T511 and a first axial protrusion T512, similar to the second embodiment. However, in this embodiment, unlike the second embodiment, the first protrusion T51 includes a plurality of first radial protrusions T511. The plurality of first radial protrusions T511 intersect with the first axial protrusion T512 and are arranged so as to be spaced apart in the axial direction.

[0063] In this embodiment, the protrusion T50 has, as shown in Figure 5A, a second protrusion T52, unlike in the second embodiment, a second radial protrusion T521 and a second axial protrusion T522. The second radial protrusion T521 extends radially from the turbine rotor 43 in the leg piece 520. In contrast, the second axial protrusion T522 extends axially from the turbine rotor 43 in the leg piece 520. In this embodiment, the second protrusion T52 includes a plurality of second axial protrusions T522. The plurality of second axial protrusions T522 intersect with the second radial protrusion T521 and are arranged radially spaced apart.

[0064] In the heat shield piece 500 of this embodiment, the recess R50 includes a first recess R51 and a second recess R52, as shown in Figure 5B.

[0065] In the recess R50 of this embodiment, the first recess R51, as shown in Figure 5B, has a first radial recess R511 and a first axial recess R512, similar to the second embodiment. However, in this embodiment, unlike the second embodiment, the first recess R51 includes a plurality of first radial recesses R511. The plurality of first radial recesses R511 intersect with the first axial recess R512 and are arranged in a line with space between them in the axial direction.

[0066] In the recess R50 of this embodiment, the second recess R52, as shown in Figure 5B, differs from the second embodiment in that it has a second radial recess R521 and a second axial recess R522. The second radial recess R521 extends radially from the turbine rotor 43 in the leg piece 520. In contrast, the second axial recess R522 extends axially from the turbine rotor 43 in the leg piece 520. In this embodiment, the second recess R52 includes a plurality of second axial recesses R522. The plurality of second axial recesses R522 intersect with the second radial recess R521 and are arranged radially spaced apart.

[0067] [B] Summary As described above, in the heat shield piece 500 of this embodiment, the first protrusion T51 constituting the protrusion T50 has a first radial protrusion T511 and a first axial protrusion T512. And in the heat shield piece 500 of this embodiment, the first recess R51 constituting the recess R50 has a first radial recess R511 and a first axial recess R512. In this embodiment, there are multiple first radial protrusions T511, and these multiple first radial protrusions T511 are arranged in a line with space between them in the axial direction. Similarly, there are multiple first radial recesses R511, and these multiple first radial recesses R511 are arranged in a line with space between them in the axial direction.

[0068] Furthermore, in this embodiment, the second convex portion T52 constituting the convex portion T50 has a second radial convex portion T521 and a second axial convex portion T522, and the second recess R52 constituting the recess R50 has a second radial recess R521 and a second axial recess R522. There are multiple second axial convex portions T522, and these multiple second axial convex portions T522 are arranged radially spaced apart. Similarly, there are multiple second axial recesses R522, and these multiple second axial recesses R522 are arranged radially spaced apart.

[0069] Therefore, in this embodiment, the shape of the gap between the convex portion T50 and the concave portion R50 is more complex than in the second embodiment, so the cooling fluid CF passing through the gap between the convex portion T50 and the concave portion R50 experiences increased pressure loss. As a result, in this embodiment, leakage of the cooling fluid CF from the upstream space SU to the downstream space SD can be suppressed more effectively than in the second embodiment.

[0070] <Fourth Embodiment> [A] Composition of heat shield piece 500 Figure 6 shows an enlarged view of the space between a pair of heat-shielding pieces 500 that are adjacent to each other in the rotational direction R in the heat-shielding member 50 of the fourth embodiment. In Figure 6, similar to Figure 3C, the portion between the pair of heat-shielding plate pieces 510 that constitute the heat-shielding plate 51 in the heat-shielding piece 500 (part X in Figure 8B) is shown in an enlarged view.

[0071] As shown in Figure 6, in this embodiment, the shape of the first protrusion T51 and the shape of the first recess R51 formed on the heat shield piece 510 differ from those in the first embodiment described above (see Figure 3C). Except for this point and related points, this embodiment is the same as the first embodiment described above, so the explanation of overlapping parts will be omitted as appropriate.

[0072] In this embodiment, as shown in Figure 6, the first protrusion T51 formed on the heat shield piece 510 has a curved surface with an arc shape at its tip, unlike in the first embodiment (see Figure 3C). Similarly, the first recess R51 formed on the heat shield piece 510 has a curved surface with an arc shape, unlike in the first embodiment (see Figure 3C), similar to the shape of the tip of the first protrusion T51.

[0073] Although not shown in the illustration, the second protrusion T52 and second recess R52 formed on the pair of leg pieces 520 that constitute the leg portion 52 of the heat shield piece 500 are configured in a similar manner.

[0074] [B] Summary Therefore, in this embodiment, the convex portion T50 can be easily inserted into the concave portion R50 between the multiple heat shield pieces 500, and thus the heat shield member 50 can be easily assembled from the multiple heat shield pieces 500.

[0075] <Fifth Embodiment> [A] Composition of heat shield piece 500 Figure 7 shows an enlarged view of the space between a pair of heat-shielding pieces 500 that are adjacent to each other in the rotational direction R in the heat-shielding member 50 of the fifth embodiment. In Figure 7, similar to Figure 3C, the portion between the pair of heat-shielding plate pieces 510 that constitute the heat-shielding plate 51 in the heat-shielding piece 500 (part X in Figure 8B) is shown in an enlarged view.

[0076] As shown in Figure 7, in this embodiment, the first protrusion T51 and the first recess R51 formed on the heat shield piece 510 are multiple, unlike in the first embodiment described above (see Figure 3C). Except for this point and related points, this embodiment is the same as the first embodiment described above, so the explanation of overlapping parts will be omitted as appropriate.

[0077] In this embodiment, as shown in Figure 7, the multiple first protrusions T51 formed on the heat shield piece 510 are arranged so as to be spaced apart in the axial direction. Similarly, the multiple first recesses R51 formed on the heat shield piece 510 are arranged so as to be spaced apart in the axial direction.

[0078] Although not shown in the illustration, the second protrusions T52 and second recesses R52 formed on the pair of leg pieces 520 constituting the leg portion 52 of the heat shield piece 500 may also be multiple.

[0079] [B] Summary As a result, in this embodiment, the shape of the gap between the convex portion T50 and the concave portion R50 is more complex than in the second embodiment, so the cooling fluid CF passing through the gap between the convex portion T50 and the concave portion R50 experiences increased pressure loss. Consequently, in this embodiment, leakage of the cooling fluid CF from the upstream space SU to the downstream space SD can be suppressed more effectively than in the second embodiment.

[0080] <Other>

[0081] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims and their equivalents. [Explanation of symbols]

[0082] 4: Turbine, 41: Casing, 41a: Inner casing, 41b: Outer casing, 43: Turbine rotor, 45: Stationary blades, 46: Rotating blades, 47: Turbine stages, 50: Heat shield member, 51: Heat shield plate, 52: Legs, 61: Seal pin, 62: Seal pin, 411: Gas supply pipe, 412: Exhaust pipe, 421: Inlet sleeve, 422: Nozzle box, 431: Rotor body, 432: Rotor disc, 451: Diaphragm inner ring, 451f: Seal fin, 461: Mounting part, 500: Heat shield piece, 510: Heat shield plate piece, 520: Leg piece, AX: Rotating shaft, Bw: Rear side, CF: Cooling fluid, Ds: Downstream side, Fw: Front side, LC: Communication Path, M: working medium, R: rotational direction, R50: recess, R51: first recess, R51: recess, R510: recess, R511: first radial recess, R512: first axial recess, R52: second recess, R520: recess, R521: second radial recess, R522: second axial recess, SB: rear end face, SD: downstream space, SF: front end face, SP: space, SU: upstream space, T50: convex part, T51: first convex part, T511: first radial convex part, T512: first axial convex part, T52: second convex part, T521: second radial convex part, T522: second axial convex part, TR: engaged groove, Us: upstream side, x: first horizontal direction, y: second horizontal direction, z: vertical direction,

Claims

1. Casing and, A turbine rotor, housed in the aforementioned casing, rotates as a working fluid flows axially along the axis of rotation, A turbine stage including stationary blades installed inside the casing and rotor blades installed on the outer surface of the turbine rotor, A turbine comprising, wherein a plurality of turbine stages are provided in the axial direction, A heat shield member is formed by arranging a plurality of heat shield pieces in the direction of rotation of the turbine rotor on the outer surface of the turbine rotor that faces the stationary blades. It has, Each of the aforementioned heat shielding pieces is The front end face located on the front side in the direction of rotation, The rear end face located on the rear side in the aforementioned rotational direction and Includes, A protrusion is provided on one of the front end face and the rear end face. A recess is provided on the other of the front end face and the rear end face. The aforementioned protrusion is formed integrally with the heat shield piece. The arrangement is such that the spaces between each of the multiple heat-shielding pieces are sealed by having the protrusions accommodate the recesses between them. The heat shielding member is The leg portion is engaged with an engagement groove formed on the outer circumferential surface of the turbine rotor, A heat shield located on the outer part of the leg portion and It has, The leg portion is configured to divide an upstream space located on the upstream side in the axial direction and a downstream space located on the downstream side. The configuration is such that the protrusions between each of the plurality of heat shield pieces are accommodated in the recesses, thereby sealing the space between the upstream space and the downstream space and preventing leakage of cooling fluid from the upstream space to the downstream space. Turbine.

2. Each of the aforementioned heat shielding pieces is The leg pieces that constitute the leg portion, The heat shield plate pieces that constitute the heat shield plate and Includes, The aforementioned protrusion is, The first protrusion provided on one of the heat shield pieces and The leg piece has a second protrusion provided on one of its surfaces and Includes, The aforementioned recess is The first recess provided on the other surface of the heat shield piece and The leg piece has a second recess provided on the other surface and Includes, Between each of the plurality of heat shielding pieces, the first protrusion is housed in the first recess and the second protrusion is housed in the second recess. The turbine according to claim 1.

3. The first convex portion is, The heat shield plate piece includes a first radial projection extending in the radial direction of the turbine rotor, The heat shield plate piece has a first axial projection that extends in the axial direction of the turbine rotor and Includes, The first recess is, The heat shield plate piece has a first radial recess extending in the radial direction of the turbine rotor, The heat shield plate piece has a first axial recess extending in the axial direction of the turbine rotor and including, The turbine according to claim 2.

4. The first protrusion includes a plurality of first radial protrusions, and the plurality of first radial protrusions are arranged in the axial direction with spaces between them. The first recess includes a plurality of first radial recesses, and the plurality of first radial recesses are arranged with space between them in the axial direction. The turbine according to claim 3.

5. The second convex portion is, The leg piece includes a second radial projection extending in the radial direction of the turbine rotor, The leg piece has a second axial projection that extends in the axial direction of the turbine rotor and Includes, The second recess is, The leg piece includes a second radial recess extending in the radial direction of the turbine rotor, In the leg piece, a second axial recess extending in the axial direction of the turbine rotor and including, The turbine according to any one of claims 2 to 4.

6. The second protrusion includes a plurality of second axial protrusions, and these plurality of second axial protrusions are arranged so as to be spaced apart in the radial direction. The second recess includes a plurality of second axial recesses, and these plurality of second axial recesses are arranged spaced apart in the radial direction. The turbine according to claim 5.

7. A heat shielding device for a turbine comprising a casing, a turbine rotor housed in the casing and rotating by the flow of a working medium in the axial direction along the axis of rotation, and turbine stages including stationary blades installed inside the casing and rotor blades installed on the outer circumferential surface of the turbine rotor, wherein a plurality of turbine stages are provided in the axial direction, A heat shield member is formed by arranging a plurality of heat shield pieces in the direction of rotation of the turbine rotor on the outer surface of the turbine rotor that faces the stationary blades. It has, Each of the aforementioned heat shielding pieces is The front end face located on the front side in the direction of rotation, The rear end face located on the rear side in the aforementioned rotational direction and Includes, A protrusion is provided on one of the front end face and the rear end face. A recess is provided on the other of the front end face and the rear end face. The arrangement is such that the spaces between each of the multiple heat-shielding pieces are sealed by having the protrusions accommodate the recesses between them. The heat shielding member is The leg portion is engaged with an engagement groove formed on the outer circumferential surface of the turbine rotor, A heat shield located on the outer part of the leg portion and It has, The leg portion is configured to divide an upstream space located on the upstream side in the axial direction and a downstream space located on the downstream side. The configuration is such that the protrusions between each of the plurality of heat shield pieces are accommodated in the recesses, thereby sealing the space between the upstream space and the downstream space and preventing leakage of cooling fluid from the upstream space to the downstream space. Heat shielding device.

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