JP6621303B2 - Seal member and method for manufacturing seal member - Google Patents

Description

  The present invention relates to a seal member used for, for example, a steam turbine and a gas turbine, and a method for manufacturing the seal member.

  Conventionally, a leaf seal as a shaft seal member that seals the periphery of a rotating shaft has been used in rotating devices such as a gas turbine, a steam turbine, and a compressor (see, for example, Patent Document 1). In this leaf seal, the thickness of the leaf group on the low pressure space side relative to the leaf group in which a plurality of leaf seals are arranged in an annular shape is made larger than that on the high pressure space side, thereby reducing the pressure drop in the leaf group. As occurring on the space side, the gap between the leaves on the low pressure space side is reduced.

JP2013-238111A

  By the way, in the conventional leaf seal, the gap between the leaves of the leaf group is not uniform, and the sealed fluid may enter the gap between the specific leaf seal and the leaf seal near the specific leaf seal. In such a case, vibration propagation due to the spring rigidity of the sealed fluid causes fluttering at the tip of the leaf seal and excessive stress acts on it, so that fatigue damage may occur at the tip of the leaf seal. is there.

  The present invention has been made in view of such circumstances, and provides a seal member that can improve the rigidity of the leaf group and can prevent fatigue damage of the shaft seal member, and a method for manufacturing the seal member. Objective.

  The seal member of the present invention is a seal member formed by laminating flexible plate-like members in an annular shape, and the member can be etched with a first metal plate containing a first metal material. A second metal plate containing a second metal material is laminated, and the thickness on one end side is relatively smaller than the thickness on the other end side.

  According to the sealing member of the present invention, since the second metal plate contains the second metal material that can be etched, the thickness of the one end side and the other end side of the sealing member can be made different by the etching process. It becomes. Thereby, since the sealing member can improve the rigidity in the one end side of a sealing member, it becomes possible to prevent the fatigue damage at the time of use of a sealing member.

  In the sealing member of the present invention, it is preferable that the thickness of the plate member decreases from the one end side toward the other end side. With this configuration, the seal member can further improve the rigidity at the one end side of the seal member, so that it is possible to further prevent fatigue damage during use of the seal member.

  In the sealing member of this invention, it is preferable that the said plate-shaped member was provided with the convex-shaped part on the surface of the 2nd metal plate. According to this configuration, the seal member can obtain a damper effect when the seal member comes into contact with an adjacent seal member during use, and thus can further prevent fatigue damage during use of the seal member.

  In the sealing member of the present invention, it is preferable that the first metal plate is sandwiched between a pair of the second metal plates. With this configuration, the seal member can further improve the rigidity at the one end side of the seal member, so that it is possible to further prevent fatigue damage during use of the seal member.

  In the sealing member of the present invention, it is preferable that the first metal material contains a Ni-based alloy in which the total content of aluminum and titanium is 1% by mass or more. With this configuration, high-temperature strength and oxidation resistance that can be used at a high temperature of 600 ° C. can be provided, so that the floating performance of the leaf accompanying the fixation of the leaves by the oxide scale that can occur in the gap between the leaves. It becomes possible to prevent the leaf and the rotor from coming into contact with each other due to the decrease in the height. In addition, as the Ni-based alloy, a precipitation-type Ni-based alloy whose high-temperature strength is improved by aging treatment is preferable from the viewpoint of further improving the above-described effects.

  In the sealing member of the present invention, the second metal material is made of at least one of stainless steel and Ni-based alloy having a chromium content of 10% by mass or more and a molybdenum content of less than 3% by mass. It is preferable to include. With this configuration, the oxidation resistance at a high temperature of 600 ° C. can be improved and the deterioration of the etching processing accuracy due to the excessive increase in the corrosion resistance against the etching solution can be prevented. Accurate etching can be performed, and processing in the thickness direction of the seal member into an arbitrary shape is facilitated.

  A manufacturing method of a sealing member of the present invention is a manufacturing method of a sealing member formed by laminating flexible plate-like members, and includes a first metal plate containing a first metal material, and a first metal plate that can be etched. A lamination step of laminating a second metal plate containing two metal materials, and etching the second metal plate so that the thickness on one end side of the second metal plate is relative to the thickness on the other end side. And an etching step for obtaining a shaft seal member reduced in size.

  According to the method for manufacturing a seal member of the present invention, since the second metal plate contains the second metal material that can be etched, the thickness at one end side of the seal member is made different from the thickness at the other end side by the etching process. It becomes possible. Thereby, since the sealing member obtained by the manufacturing method of a sealing member can improve the rigidity in the one end side of a sealing member, it becomes possible to prevent the fatigue damage at the time of use of a sealing member.

  ADVANTAGE OF THE INVENTION According to this invention, the rigidity of a leaf group can be improved and the manufacturing method of the sealing member which can prevent the fatigue damage of a shaft seal member, and a sealing member is realizable.

FIG. 1 is a schematic diagram illustrating an example of a gas turbine system according to an embodiment of the present invention. FIG. 2 is a cross-sectional view schematically showing the shaft seal device according to the embodiment of the present invention. FIG. 3 is a perspective view schematically showing a part of the shaft seal device according to the embodiment of the present invention. FIG. 4 is a cross-sectional view schematically showing the shaft seal device according to the embodiment of the present invention. FIG. 5 is an exploded view of the shaft seal device according to the embodiment of the present invention. FIG. 6A is a plan view showing an example of a leaf according to the embodiment of the present invention. 6B is a cross-sectional view taken along the line VIB-VIB in FIG. 6A. 6C is a cross-sectional view taken along the line VIC-VIC in FIG. 6A. 6D is a cross-sectional view taken along line VIC-VIC in FIG. 6A. FIG. 7A is a plan view showing another example of the leaf according to the embodiment of the present invention. 7B is a cross-sectional view taken along the line VIIB-VIIB in FIG. 7A. FIG. 7C is a cross-sectional view taken along line VIIC-VIIC in FIG. 7A. FIG. 8A is a plan view showing another example of the leaf according to the embodiment of the present invention. 8B is a cross-sectional view taken along line VIIIB-VIIIB in FIG. 8A. 8C is a cross-sectional view taken along line VIIIC-VIIIC in FIG. 8A. FIG. 9 is an explanatory diagram of fluid flow when a general shaft seal device is used. FIG. 10 is an explanatory view of a leaf when a general shaft seal device is used. FIG. 11 is an explanatory view of a leaf when the shaft seal device according to the embodiment of the present invention is used. FIG. 12 is a diagram illustrating the relationship between the chromium (Cr) content and the molybdenum (Mo) content in the second metal material. FIG. 13 is a flowchart of the leaf seal manufacturing method according to the embodiment of the present invention. FIG. 14A is an explanatory diagram of the leaf seal manufacturing method according to the embodiment of the present invention. FIG. 14B is an explanatory diagram of the leaf seal manufacturing method according to the embodiment of the present invention. FIG. 14C is an explanatory diagram of the leaf seal manufacturing method according to the embodiment of the present invention.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In addition, it is not limited to each following embodiment, It can implement by changing suitably. Also, the following embodiments can be implemented in combination as appropriate. Moreover, the same code | symbol is attached | subjected to the component which is common in each embodiment, and duplication of description is avoided.

  FIG. 1 is a schematic diagram illustrating an example of a gas turbine system 1 including a rotating machine according to an embodiment of the present invention. As shown in FIG. 1, the gas turbine system 1 supplies fuel to a compressor (rotary machine) 2 that compresses air G1 into compressed air G2, and compressed air G2 compressed by the compressor 2. Combustor 3 to be mixed and combusted, turbine (rotary machine) 4 to which combustion gas G3 combusted in combustor 3 is supplied, rotary shaft 51 disposed in compressor 2 and turbine 4 And a rotor 5 having a rotating shaft 50 connecting the rotating shaft 52.

  The compressor 2 has a casing 2K into which air G1 is introduced into the internal space. The compressor 2 compresses the air introduced into the internal space of the casing 2K to form compressed air G2. The compressor 2 is provided with a support portion 2S having a bearing that rotatably supports the rotary shaft 50.

  The turbine 4 has a casing 4K into which the combustion gas G3 is introduced into the internal space. The turbine 4 converts the thermal energy of the combustion gas G3 into rotational energy by introducing the combustion gas G3 generated in the combustor 3 into the internal space of the casing 4K and expanding it. The turbine 4 is provided with a support portion 4S having a bearing that rotatably supports the rotary shaft 50.

  The rotor 5 includes a moving blade 51A provided on the rotating shaft 51 disposed in the internal space of the casing 2K, and a moving blade 52A provided on the rotating shaft 52 disposed in the internal space of the casing 4K.

  The compressor 2 has a stationary blade 2A arranged in the casing 2K. A plurality of stationary blades 2A of the compressor 2 and moving blades 51A provided on the rotating shaft 51 are alternately arranged in a direction parallel to the axial direction of the axis AX of the rotating shaft 50.

  The turbine 4 has a stationary blade 4A disposed in the casing 4K. A plurality of stationary blades 4 </ b> A of the turbine 4 and moving blades 52 </ b> A provided on the rotating shaft 52 are alternately arranged in the axial direction of the rotating shaft 50.

  The gas turbine system 1 is disposed in the inner peripheral portion of the stationary blade 2 </ b> A in the casing 2 </ b> K of the compressor 2, and is disposed in the casing 4 </ b> K of the turbine 4 and the shaft seal device 10 that seals the periphery of the rotating shaft 51. And a shaft sealing device 10 for sealing the periphery of the rotating shaft 52. The shaft seal device 10 disposed in the compressor 2 prevents the compressed air G2 that is a working gas from leaking from the high-pressure space side to the low-pressure space side. Moreover, the shaft seal device 10 of the compressor 2 is disposed on the support portion 2S. The shaft seal device 10 disposed in the turbine 4 suppresses the combustion gas that is the working gas from leaking from the high pressure side to the low pressure side. The shaft seal device 10 of the turbine 4 is disposed on the inner peripheral portion of the stationary blade 4A. Further, the shaft seal device 10 of the turbine 4 is disposed in the support portion 4S.

  In the gas turbine system 1, the combustion gas G <b> 3 introduced from the combustor 3 is supplied to the moving blade 52 </ b> A in the turbine 4. As a result, the thermal energy of the combustion gas G3 is converted into mechanical rotational energy to generate power. Part of the power generated in the turbine 4 is transmitted to the compressor 2 via the rotating shaft 50. A part of the power generated in the turbine 4 is used as power for the compressor 2.

  Next, the shaft seal device 10 according to the present embodiment will be described with reference to FIG. FIG. 2 is a schematic cross-sectional view illustrating an outline of the shaft seal device 10 according to the present embodiment. FIG. 3 is a perspective view schematically illustrating a part of the shaft seal device 10 according to the present embodiment. FIG. 4 is a cross-sectional view schematically showing the shaft seal device 10 including the axis AX of the rotating shaft 50 according to the present embodiment. FIG. 5 is an exploded view of the shaft seal device 10 according to the present embodiment. 2 shows a cross-sectional view taken along line AA in FIG. 1, and FIG. 3 shows a part of the shaft seal device 10 in a cutaway manner.

  In the following description, the shaft seal device 10 provided in the turbine 4 among the shaft seal devices 10 provided in the compressor 2 and the turbine 4 will be described. The configuration of the shaft seal device 10 provided in the compressor 2 is the same as the configuration of the shaft seal device 10 provided in the turbine 4.

  As shown in FIGS. 2 to 5, as shown in FIG. 2, the shaft seal device 10 has a plurality of seal segments 11 arranged around the rotation shaft 52. Each seal segment 11 has an arc shape in a plane orthogonal to the axis AX. In the present embodiment, eight seal segments 11 are arranged around the rotation shaft 50.

  The seal segment 11 includes a plurality of leaves (plate members: seal members) 20 disposed around the rotation shaft 50, a holding member 134 including a holding ring 13 and a holding ring 14 that hold the leaf 20, The back spacer 15 disposed between the holding member 134, the high-pressure side side seal plate 16 disposed on one end side of the leaf 20 in the axial direction D1 of the rotating shaft 50, and the leaf 20 in the axial direction D1 of the rotating shaft 50. And a low-pressure side side seal plate 17 disposed on the other end side.

  The seal segment 11 is inserted into the recess 9 a of the housing 9 corresponding to the stationary blade 4 </ b> A, and at least a part thereof is disposed in the recess 9 a of the housing 9. The recess 9 a has an opening 9 k that faces the outer peripheral surface of the rotation shaft 52. The recess 9a extends in the circumferential direction D2 of the rotating shaft 50. A part of the leaf 20 protrudes outside the recess 9a. The housing 9 is also provided in each of the stationary blade 2A, the support portion 2S, and the support portion 4S.

  The leaf 20 is a plate-like member having flexibility in the circumferential direction D2 of the rotation shaft 52 and can be elastically deformed. In the present embodiment, the leaf 20 is a thin steel plate. The normal line of the surface of the leaf 20 is substantially parallel to the circumferential direction D2 that is the rotation direction of the rotation shaft 52. The width direction of the leaf 20 substantially coincides with the axial direction of the rotation shaft 52. The thickness direction of the leaf 20 substantially coincides with the circumferential direction D2 of the rotating shaft 52. With such a configuration, the leaf 20 has high rigidity in the axial direction D1 of the rotation shaft 52.

  A plurality of the leaves 20 are arranged at intervals in the circumferential direction D2 of the rotating shaft 52. A gap S is formed between the leaf 20 and the leaf 20 adjacent to the leaf 20. A leaf laminate 12 that is an aggregate (laminated body) in which a plurality of leaves 20 are laminated by the plurality of leaves 20 is formed.

  The leaf laminate 12 composed of a plurality of leaves 20 seals the periphery of the rotating shaft 52 to divide the space around the rotating shaft 52 into two spaces in the axial direction D1 of the rotating shaft 52. In the present embodiment, the leaf laminate 12 divides the space around the rotating shaft 52 into a high-pressure space and a low-pressure space whose pressure is relatively lower than that of the high-pressure space.

  The plurality of leaves 20 includes an outer base end portion (outer end portion) 20a in the radial direction D3 orthogonal to the axis AX of the rotation shaft 52, an inner distal end portion (inner end portion) 20b, and the rotation shaft 50. It has a side end 20c on the high pressure space side in the axial direction and a side end 20d on the low pressure space side.

  In the following description, the base end portions 20a of the plurality of leaves 20 are also referred to as the base end portion 12a of the leaf laminate 12, and the tip portions 20b of the plurality of leaves 20 are combined to be the tip end portions 12b of the leaf laminate 12. The side end portions 20c of the plurality of leaves 20 are collectively referred to as the side end portions 12c of the leaf laminate 12, and the side end portions 20d of the plurality of leaves 20 are collectively referred to as the side end portions 12d of the leaf laminate 12. The base end portion 12a is an aggregate of a plurality of base end portions 20a. The tip portion 12b is an aggregate of a plurality of tip portions 20b. The side end portion 12c is an aggregate of a plurality of side end portions 20c. The side end portion 12d is an aggregate of a plurality of side end portions 20d.

  The base end portion 12 a is directed outward in the radial direction of the rotation shaft 52. The distal end portion 12 b is directed inward in the radial direction of the rotation shaft 52 so as to face the outer peripheral surface of the rotation shaft 52. Moreover, the front-end | tip part 12b (front-end | tip part 20b) is arrange | positioned on the outer side of the recessed part 9a through the opening 9k. The side end portion 12 c is directed to the high-pressure space side that is one end side in the axial direction of the rotating shaft 52. The side end portion 12d is directed to the low-pressure space side that is the other end side in the axial direction of the rotating shaft 52.

  In the present embodiment, the base end portions 20a of the plurality of leaves 20 are respectively fixed to the back spacer 15 and become fixed ends. Moreover, the front-end | tip part 20b of the some leaf 20 becomes a free end which is not fixed, respectively. The plurality of leaves 20 (leaf laminated body 12) are held by the holding member 134 in a state where the base end portion 20a is fixed.

  The leaf 20 includes a head portion 21 provided with a base end portion 20a, and a body portion 22 provided with a distal end portion 20b, a side end portion 20c, and a side end portion 20d and capable of elastic deformation. The size of the body portion 22 in the width direction of the leaf 20 that is the axial direction of the rotation shaft 52 is smaller than the size of the head portion 21. The dimension of the trunk portion 22 in the thickness direction, which is the circumferential direction of the rotating shaft 52, is smaller than the dimension of the head portion 21. The body part 22 is provided with a notch part 20x and a notch part 20y at a boundary part between the body part 22 and the head part 21. The head portion 21 includes a side protrusion portion 21c and a side protrusion portion 21d in which the base end portion 20a side protrudes in the width direction from the notch portion 20x and the notch portion 20y. In this Embodiment, the some leaf 20 is connected by welding in each of the side protrusion part 21c of the head 21, and the side protrusion part 21d.

  The holding member 134 is supported by the housing 9 and holds the leaf laminate 12. The housing 9 has a support surface 9s that supports the holding member 134 inside the recess 9a. The holding member 134 is supported by the support surface 9s.

  The holding member 134 includes a holding ring 13 and a holding ring 14 that are arcuate members extending in the circumferential direction D2 of the rotating shaft 52. The holding ring 13 has a recess 13 a in which a part of the head 21 including the side protrusion 21 c of the leaf 20 is disposed. The holding ring 14 has a recess 14 a in which a part of the head 21 including the side protrusion 21 d of the leaf 20 is disposed. The back spacer 15 is disposed between the head 21 of the leaf 20 and the holding ring 13 and the holding ring 14. In the leaf 20, the head 21 is fitted into the recess 13 a and the recess 14 a through the back spacer 15. As a result, the leaf laminate 12 is held by the holding member 134.

  The high-pressure side side seal plate 16 is disposed in the high-pressure space so as to be adjacent to the leaf 20 (leaf laminated body 12). The low-pressure side side seal plate 17 is disposed in the low-pressure space so as to be adjacent to the leaf 20 (leaf laminated body 12). The high-pressure side seal plate 16 is disposed so as to face a part of the side end 12c of the leaf laminate 12 in the high-pressure space. The low-pressure side side seal plate 17 is disposed so as to face a part of the side end portion 12d of the leaf laminate 12 in the low-pressure space.

  The high-pressure side side seal plate 16 includes a facing surface 161 that faces at least a part of the side end portion 20c of the leaf 20 (side end portion 12c of the leaf laminate 12), and a surface 162 that faces the opposite direction of the facing surface 161. Have. The high-pressure side side seal plate 16 has a convex portion 16 a that is disposed in the cutout portion 20 x of the leaf 20. The convex portion 16 a arranged in the notch 20 x is fixed by the leaf 20 (leaf laminated body 12) and the holding ring 13.

  In the present embodiment, the distal end portion 163 of the high-pressure side seal plate 16 is farther from the rotating shaft 52 than the distal end portion 20 b of the leaf 20. The high-pressure side seal plate 16 opposes a part of the side end 20c (side end 12c) on the base end 20a side in the radial direction, and the side end 20c (side end 12c) on the distal end 20b side. It does not face part.

  The low-pressure side side seal plate 17 includes a facing surface 171 that faces at least a part of the side end portion 20d of the leaf 20 (side end portion 12d of the leaf laminate 12), and a surface 172 that faces the opposite direction of the facing surface 171. Have. The low-pressure side side seal plate 17 has a convex portion 17 a disposed in the cutout portion 20 y of the leaf 20. The convex portion 17 a arranged in the notch 20 y is fixed by the leaf 20 (leaf laminated body 12) and the holding ring 14.

  In the present embodiment, the distal end portion 173 of the low-pressure side side seal plate 17 is farther from the rotating shaft 52 than the distal end portion 20 b of the leaf 20. The low-pressure-side side seal plate 17 faces a part of the side end 20d (side end 12d) on the base end 20a side in the radial direction, and the side end 20d (side end 12d) on the tip 20b side. Arranged so as not to face part.

  Further, in the present embodiment, the distal end portion 173 of the low pressure side side seal plate 17 is farther from the rotating shaft 52 than the distal end portion 163 of the high pressure side seal plate 16. In the present embodiment, the dimension of the high-pressure side seal plate 16 is larger than the dimension of the low-pressure side seal plate 17 in the radial direction D3 of the rotating shaft 52.

  Next, the leaf 20 according to the present embodiment will be described in detail with reference to FIGS. 6A to 6D. 6A is a plan view showing an example of the leaf 20 according to the present embodiment, FIG. 6B is a cross-sectional view taken along the line VIB-VIB of FIG. 6A, and FIGS. 6C and 6D are views of FIG. It is arrow sectional drawing in a VIC-VIC line.

  As shown in FIGS. 6A to 6D, the leaf 20 according to the present embodiment is a flexible plate-like member, and has high temperature strength and oxidation resistance at a high temperature (for example, 500 ° C. or more and 700 ° C. or less). The first metal plate 201 containing the first metal material having the above and the second metal plate 202 containing the second metal material that has oxidation resistance and can be etched are laminated. In this leaf 20, the thickness d1 of the side end portion 20c on one end side of the leaf 20 arranged on the high pressure space side is relative to the thickness d2 of the side end portion 20d on the other end side arranged on the low pressure space side. Is formed small. The thickness d3 of the first metal plate 201 is substantially uniform. In the present embodiment, the first metal plate 201 and the second metal plate 202 are made into a clad structure material by rolling and pressure bonding, and then the other end side of the second metal plate 202 is etched to etch the second metal plate 202. The thickness d4 on the other end side is made smaller than the thickness d5 on the one end side. Thus, by laminating the first metal plate 201 excellent in high-temperature strength and oxidation resistance and the second metal plate 202 that has oxidation resistance and can be etched, the oxidation resistance of the leaf 20 at high temperature and The thickness of the second metal plate 202 can be changed by etching without impairing the strength. Thereby, since the leaf 20 can increase the rigidity of the leaf 20 on the low pressure space side, it becomes possible to prevent fatigue damage when the leaf 20 is used. The difference between the thickness d4 and the thickness d5 is selected so that the gap between the leaves is, for example, a difference between 0 μm and 100 μm.

  The thickness of the leaf 20 is not particularly limited as long as the thickness decreases from one end side to the other end side. The leaf 20 may have a tapered shape in which the thickness continuously decreases from one end side toward the other end side (see FIG. 6C), and the thickness changes stepwise from the one end side toward the other end side. It may be a shape (see FIG. 6D). Among these, the thickness of the leaf 20 is continuous from one end side to the other end side from the viewpoint of improving the flexibility of the leaf 20 and reducing leakage loss when the shaft seal device 10 is used. From the viewpoint of facilitating the etching process at the time of manufacturing the leaf 20, a shape whose thickness changes stepwise from one end side to the other end side is preferable.

  7A is a plan view illustrating another example of the leaf 20 according to the present embodiment, FIG. 7B is a cross-sectional view taken along the line VIIB-VIIB in FIG. 7A, and FIG. 7C is a VIIC in FIG. 7A. It is arrow sectional drawing in the -VIIC line.

  The leaf 20 shown in FIG. 7A is laminated on a first metal plate 201 containing a first metal material having high temperature strength and oxidation resistance, and on one main surface of the first metal plate 201, and has oxidation resistance. And a second metal plate 202A containing a second metal material that can be etched and laminated on the other main surface of the first metal plate 201, and has a corrosion-resistant second metal material that can be etched. The second metal plate 202B is laminated. This leaf 20 is the other end where the thickness d1 of the side end portion 20c on one end side of the leaf 20 arranged on the high pressure space side is arranged on the low pressure space side, like the leaf 20 shown in FIGS. 6A to 6D. It is formed relatively small with respect to the side thickness d2. The thickness d3 of the first metal plate 201 is substantially uniform.

  In the present embodiment, after the first metal plate 201, the second metal plate 202A, and the second metal plate 202B are made into a clad structure material by rolling and pressure bonding, in addition to the second metal plate 202A and the second metal plate 202B, Each end side is etched to make the thickness d4 on one end side of the second metal plate 202A smaller than the thickness d5 on the other end side, and the thickness d6 on one end side of the second metal plate 202B is made smaller on the one end side. Decrease with respect to the thickness d7. By sandwiching the first metal plate 201 between the pair of second metal plates 202A and 202B in this way, the strength of one end side of the leaf 20 disposed on the low-pressure space side can be further increased. The rigidity can be further improved and fatigue damage can be reduced. In the example shown in FIGS. 7A to 7C, the example in which the pair of second metal plates 202A and 202B is etched has been described. However, the pair of second metal plates 202A and 202B is not necessarily etched, and at least One of the second metal plate 202A and the second metal plate 202B may be etched. Further, the thickness of the second metal plates 202A and 202B may change continuously from one end side to the other end side of the leaf 20 or may change stepwise.

  8A is a plan view showing another example of the leaf 20 according to the present embodiment, FIG. 8B is a cross-sectional view taken along line VIIIB-VIIIB in FIG. 8A, and FIG. 8C is a VIIIC in FIG. 8A. It is arrow sectional drawing in the -VIIIC line | wire. As shown in FIGS. 8A to 8C, the leaf 20 is provided with a recess 202b on the surface 202a of the second metal plate 202 in addition to the structure of the leaf 20 shown in FIG. For example, the recess 202b is provided by etching the second metal plate 202 or the like. Thus, by providing the concave portion 202b in the leaf 20 and providing the convex portion (see 202a) protruding from the bottom of the concave portion 202b on the surface 202a of the second metal plate 202, the shaft seal device 10 is adjacent to the surface 20a. Since the damper effect acts when the leaves 20 come into contact with each other and the impact acting on the leaves 20 is alleviated, fatigue damage to the leaves 20 can be further prevented. In the example shown in FIGS. 8A to 8C, the example in which the concave portion 202 b is regularly provided on the surface 202 a of the second metal plate 202 to form the concave-convex structure has been described, but the surface 202 a of the second metal plate 202 is formed. It is not always necessary to provide a concavo-convex structure. For example, irregular projections or the like may be provided on the surface 202a of the second metal plate 202 as convex portions.

  Next, the flow of the combustion gas G3 in the leaf 20 when the general shaft seal device 10 is used will be described. FIG. 9 is an explanatory diagram of the flow of the combustion gas G3 when the general shaft seal device 10 is used, and FIG. 10 is an explanatory diagram of the leaf 20 when the general shaft seal device 10 is used.

  As shown in FIG. 9, in the shaft seal device 10 according to the present embodiment, the combustion gas G3 flows between the rotating shaft 52 and the tip 20b of the leaf 20 during use, and a part of the combustion gas G3 is used. It flows from the high-pressure space side to the low-pressure space side through gaps that are unevenly generated between the leaves 20. For this reason, as shown in FIG. 10, the combustion gas G3 flowing through the leaf 20 causes a vibration propagation phenomenon based on the rigidity of the fluid spring in the leaf 20, and the tip 20b of the leaf 20 is shaken to cause the tip 20b. In some cases, excessive stress may cause fatigue damage.

  FIG. 11 is an explanatory diagram of the leaf 20 when the shaft seal device 10 according to the present embodiment is used. In the present embodiment, as described above, in the leaf 20, the thickness d1 on one end side of the leaf 20 disposed on the low-pressure space side is larger than the thickness d2 on the other end side. As a result, the torsional rigidity of the leaf 20 can be improved and fluttering of the tip 20b can be prevented, so that fatigue damage to the leaf 20 can be prevented.

  As the first metal material, a Ni-based alloy (Inconel, Hastelloy, etc.) excellent in strength and oxidation resistance at high temperatures is used. The Ni-based alloy preferably contains a Ni-based alloy having a total content of aluminum (Al) and titanium (Ti) of 1% by mass. With this configuration, the shaft seal device 10 can have high-temperature strength and oxidation resistance that can be used at a high temperature of 600 ° C., so that the leaves can be secured to each other by the oxide scale that can occur in the gaps between the leaves. Accordingly, it is possible to prevent contact between the leaf and the rotor due to a decrease in the floating performance of the leaf. Further, by using such an alloy, strength such as tensile strength, fatigue strength, and creep rupture strength is improved, and excellent oxidation resistance at high temperatures, resistance to stress corrosion cracking, and pitting corrosion can be obtained. In addition, as the Ni-based alloy, a precipitation-type Ni-based alloy whose high-temperature strength is improved by aging treatment is preferable from the viewpoint of further improving the above-described effects. In addition, the leaf 20 may be provided with a larger hardness difference than that of a single material by laminating different materials that are hardened by age hardening different from the base material.

  FIG. 12 is a diagram illustrating the relationship between the chromium (Cr) content and the molybdenum (Mo) content in the second metal material. Table 1 below shows an example of a specific example of a metal material used as the second metal material. In FIG. 12 and Table 1, when the metal material was etched for 3 minutes using the optimum etching solution for the target metal material, the one that could be etched to a uniform depth (± 10 μm) was marked with ◯. What cannot be done is marked with x. In Table 1 below, stainless steel A: SUS430, stainless steel B: SUS304, Ni-base alloy A: Hastelloy X, Ni-base alloy B: Alloy 601, Ni-base alloy C: Alloy 625, Ni-base alloy D: Nimonic The relationship between the metal content of PK33, Ni-based alloy E: Alloy X750 and Ni-based alloy F: Alloy 718 and whether or not etching is possible is shown. In FIG. 12, bal. Indicates the remainder of the metal content.

  As shown in FIG. 12 and Table 1 above, the second metal material has a chromium (Cr) content of 10 mass% or more and a molybdenum content of 3 mass% as shown in Table 1 above. It is preferable to include at least one of stainless steel and Ni-base alloy that are less than With this configuration, the shaft seal device 10 can improve the oxidation resistance at a high temperature of 600 ° C., and can prevent deterioration in etching processing accuracy due to excessive corrosion resistance against the etching solution. It is possible to perform highly accurate etching processing in the plate thickness direction, and processing in the plate thickness direction to an arbitrary shape of the seal member becomes easy. The content of Cr is preferably 10% by mass or more from the viewpoint of using a general stainless steel and from the viewpoint of oxidation resistance at a high temperature of 600 ° C. Moreover, if molybdenum (Mo) is less than 3 mass%, it can prevent the fall of the precision of the etching process of the thickness direction by the corrosion resistance with respect to an etching liquid rising too much. From the above viewpoint, as the second metal material, as stainless steel and Ni-based alloy, the Cr content is more preferably 12.5% by mass or more, further preferably 15% by mass or more, and the Mo content is 2 mass% or less is more preferable, and 1 mass% or less is still more preferable.

  Next, a method for manufacturing the leaf seal 20 according to the present embodiment will be described with reference to FIG. FIG. 13 is a flowchart of the method for manufacturing the leaf seal 20 according to the present embodiment. As shown in FIG. 13, the manufacturing method of the leaf seal 20 according to the present embodiment includes a first metal plate 201 containing a first metal material and a second metal plate containing a second metal material that can be etched. Etching to obtain the leaf seal 20 in which the thickness d4 on one end side of the second metal plate 202 is made smaller than the thickness d5 on the other end side by etching the second metal plate 202. Process ST12.

  14A to 14C are explanatory diagrams of a method for manufacturing the leaf seal 20 according to the present embodiment. As shown in FIGS. 14A and 14B, in the stacking step ST <b> 11, the first metal plate 201 having a relatively high strength with respect to the second metal plate 202 and the second metal plate 202 that can be etched are rolled and pressed. A lad structure is formed by laminating them. Next, as shown in FIG. 13C, the second metal plate 202 is etched, and the leaf 20 having a thickness d1 of the side end portion 20c on one end side is relatively smaller than the thickness d2 on the other end side 20d. Get. The etching conditions are not particularly limited, and a conventionally known etching method capable of etching a nickel-chromium-iron alloy can be applied.

  As described above, according to the shaft sealing device 10 according to the present embodiment, since the second metal plate 202 contains the second metal material that can be etched, the thickness on one end side of the leaf 20 by the etching process. It is possible to make d1 different from the thickness d2 on the other end side. Thereby, since the shaft seal device 10 can improve the torsional rigidity at one end side of the leaf 20, it is possible to prevent fatigue damage of the leaf 20 during use.

1 Gas turbine system 2 Compressor (rotary machine)
2A Stator blade 2K Casing 2S Support part 3 Combustor 4 Turbine (rotary machine)
4A Stator blade 4K Casing 5 Rotor 50, 51, 52 Rotating shaft 51A, 52A Rotor blade 9 Housing 9a Recess 9k Open 9s Support surface 10 Shaft seal device 11 Seal segment 12 Leaf laminate 12c Side end 13, 14 Holding ring 13a, 14a Concave portion 15 Back spacer 16 High-pressure side seal plate 16a Convex portion 161 Opposing surface 162 Surface 163 Tip portion 17 Low-pressure side seal plate 17a Convex portion 171 Opposing surface 172 Surface 20 Leaf 20a Base end portion (outer end portion)
20b Inner tip (inner end)
20c, 20d side end 20x, 20y notch 201 first metal plate 202, 202A, 202B second metal plate 21 head 21c, 21d side protrusion 22 trunk AX axis D1 axial direction D2 circumferential direction D3 radial direction G1 Air G2 Compressed air G3 Combustion gas d1, d2, d3, d4, d5, d6, d7 Thickness

Claims (7)

A sealing member in which plate members having flexibility are laminated in an annular shape,
The plate-like member is formed by laminating a first metal plate containing a first metal material and a second metal plate containing a second metal material that can be etched, and the thickness on one end side is the other end side. relatively rather small for the thickness of,
The second metal plate is disposed over the entire surface of the first metal plate, and has a thickness on one end side that is relatively smaller than a thickness on the other end side . The sealing member according to claim 1, wherein the thickness of the plate-like member decreases from the other end side toward the one end side.   The said plate-shaped member is a sealing member of Claim 1 or Claim 2 with which the convex-shaped part was provided in the surface of the 2nd metal plate.   The sealing member according to any one of claims 1 to 3, wherein the first metal plate is sandwiched between a pair of the second metal plates.   The sealing member according to any one of claims 1 to 4, wherein the first metal material contains a Ni-based alloy having a total content of aluminum and titanium of 1 mass% or more.   The second metal material includes at least one of stainless steel and Ni-based alloy having a chromium content of 10 mass% or more and a molybdenum content of less than 3 mass%. The seal member according to any one of the above. A method of manufacturing a sealing member in which plate members having flexibility are laminated,
A laminating step of laminating a first metal plate containing a first metal material and a second metal plate containing a second metal material that can be etched;
Etching the second metal plate to obtain a seal member in which the thickness of one end side of the second metal plate is made relatively smaller than the thickness of the other end side. Manufacturing method of sealing member.

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