Stationary vane ring and rotating machinery

Abstract

A fixed blade ring includes: a blade group having a plurality of blades arranged circumferentially along an axis; a shroud section connecting radial ends of these plurality of blades so as to connect the plurality of blades of the blade group circumferentially and having an arc shape; and a pressing section applying pressure to the blade group in a radial direction so that the blade group is pressed against the shroud section, the pressing section having a pressure distribution in which the pressure at the circumferential center in the shroud section is smaller than the pressure at both circumferential ends in the shroud section.

Description

Technical Field

[0001] The present invention relates to a stationary vane ring and a rotating machine.

[0002] This application claims priority based on Japanese Patent Application No. 2021-017268 filed on February 5, 2021, and incorporates its content herein. Background Art

[0003] Patent Document 1 discloses a stationary vane ring in which an inner peripheral shroud and an outer peripheral shroud are divided into a plurality of parts for easy assembly or disassembly, and a plurality of vanes arranged circumferentially are provided in one section.

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: Japanese Patent No. 6082285 Gazette Summary of the Invention

[0007] Technical Problem to be Solved by the Invention

[0008] In the stationary vane ring described in Patent Document 1, with respect to the central vane constrained by sections on both sides, the constraint force based on the section of the end vane unconstrained on one side becomes weak. Therefore, a difference occurs in the natural frequency of the vanes. As a result, the frequency band of the natural frequency of the entire vane becomes wide, making it difficult to avoid resonance during the operation of the rotating machine.

[0009] The present invention has been completed to solve the above problems, and an object thereof is to provide a stationary vane ring and a rotating machine capable of narrowing the frequency band of the natural frequency.

[0010] Means for Solving the Technical Problem

[0011] To solve the above problems, the stationary vane ring according to the present invention includes: a vane group having a plurality of vanes arranged circumferentially along an axis; a shroud section connecting radial ends of these plurality of vanes so as to connect the plurality of vanes of the vane group along the circumferential direction and having an arc shape extending along the circumferential direction; and a pressing section applying pressure to the vane group in the radial direction so that the vane group is pressed against the shroud section, the pressing section having a pressure distribution in which the pressure at the circumferential center in the shroud section is smaller than the pressure at the circumferential ends in the shroud section.

[0012] Moreover, the rotating machine according to the present invention includes the above stationary vane ring.

[0013] Advantageous Effects of the Invention

[0014] According to the present invention, a stationary vane ring and a rotating machine capable of narrowing the frequency band of the natural frequency can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a schematic longitudinal sectional view of a gas turbine including the stationary vane ring according to an embodiment of the present invention.

[0016] Figure 2 is the Figure 1 cross-sectional view taken along the line II-II of the first embodiment of the present invention.

[0017] Figure 3 is a view magnifying Figure 2 parts IIIa and IIIc and cross-sectional views taken along the lines IIIb-IIIb and IIId-IIId.

[0018] Figure 4 is the Figure 1 cross-sectional view taken along the line II-II of the second embodiment of the present invention.

[0019] Figure 5 is Figure 4 cross-sectional views taken along the lines Va-Va and Vb-Vb.

[0020] Figure 6 is the Figure 1 cross-sectional view taken along the line II-II of the third embodiment of the present invention.

[0021] Figure 7 is Figure 6 cross-sectional views taken along the lines VIIa-VIIa and VIIb-VIIb.

[0022] Figure 8 is the Figure 1 cross-sectional view taken along the line II-II of the first modification of the second embodiment of the present invention.

[0023] Figure 9 is the Figure 4 cross-sectional view taken along the line Va-Va of the second modification of the second embodiment of the present invention.

[0024] Figure 10 is the Figure 4 cross-sectional view taken along the line Va-Va of the third modification of the second embodiment of the present invention.

[0025] Figure 11 is a view for explaining the structure of the pressing part according to other embodiments of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0026] (First Embodiment)

[0027] (Gas Turbine)

[0028] As Figure 1 shown, the gas turbine 1 according to this embodiment includes a compressor 2 that generates compressed air, a burner 9 that generates combustion gas by mixing and burning fuel in the compressed air, and a turbine 10 driven by the combustion gas.

[0029] (Compressor)

[0030] The compressor 2 has a compressor rotor 3 that rotates around an axis O and a compressor housing 4 that covers the compressor rotor 3 from the outer peripheral side. The compressor rotor 3 has a columnar shape extending along the axis O. On the outer peripheral surface of the compressor rotor 3, a plurality of compressor rotating blade rings 5 are arranged at intervals along the axial direction A. Each compressor rotating blade ring 5 has a plurality of compressor rotating blades arranged at intervals in the circumferential direction B of the axis O on the outer peripheral surface of the compressor rotor 3. In this embodiment, the axial direction A represents the direction in which the axis O extends.

[0031] The compressor housing 4 has a cylindrical shape centered on the axis O. On the inner peripheral surface of the compressor housing 4, a plurality of compressor stationary blade rings 7 are arranged at intervals along the axial direction A. When viewed from the axial direction A, these compressor stationary blade rings 7 are alternately arranged with respect to the above-mentioned compressor rotating blade rings 5. Each compressor stationary blade ring 7 has a plurality of compressor stationary blades arranged at intervals in the circumferential direction B of the axis O on the inner peripheral surface of the compressor housing 4.

[0032] (Burner)

[0033] The burner 9 is provided between the compressor 2 and the turbine 10 that continues downstream ( Figure 1 to the right). The compressed air generated by the compressor 2 is mixed with fuel inside the burner 9 to become a premixed gas. In the burner 9, the premixed gas burns, thereby generating high-temperature and high-pressure combustion gas, and the combustion gas is led into the turbine 10.

[0034] (Turbine)

[0035] The turbine 10 has a rotor 11 that rotates around the axis O and a stator 12 that surrounds the rotor 11.

[0036] The rotor 11 has a rotating shaft 11a and a plurality of turbine rotating blade rings 20.

[0037] The rotating shaft 11a has a columnar shape extending along the axis O. The rotating shaft 11a is integrally connected to the above-mentioned compressor rotor 3 in the axial direction A, thereby forming a gas turbine rotor that rotates around the axis O.

[0038] A plurality of turbine rotating blade rings 20 are provided on the outer peripheral surface of the rotating shaft 11a and are arranged at intervals along the axial direction A.

[0039] Each turbine rotating blade ring 20 has a plurality of turbine rotating blades. The plurality of turbine rotating blades are arranged at intervals along the circumferential direction B of the axis O on the outer peripheral surface of the rotor 11.

[0040] The stator 12 has a turbine housing 15 and a plurality of fixed blade rings 13.

[0041] The turbine housing 15 is in a cylindrical shape centered on the axis O.

[0042] The plurality of fixed blade rings 13 are provided on the inner peripheral side of the turbine housing 15 and are arranged at intervals along the axial direction A. When viewed from the axial direction A, these fixed blade rings 13 are alternately arranged with respect to the above-mentioned turbine rotating blade rings 20.

[0043] Each fixed blade ring 13 has a plurality of blades 14a arranged at intervals along the circumferential direction B of the axis O near the inner peripheral surface of the turbine housing 15.

[0044] Hereinafter, with reference to Figure 2 and Figure 3 the fixed blade ring 13 of the first embodiment will be described.

[0045] (Fixed Blade Ring)

[0046] Figure 2 is Figure 1 a cross-sectional view taken along the line II-II of the fixed blade ring 13 shown.

[0047] The fixed blade ring 13 includes an outer peripheral side shroud 40, a plurality of blade groups 14, a plurality of shroud sections 43, and a pressing portion 44.

[0048] The outer peripheral side shroud 40 is a columnar structure in a ring shape centered on the axis O.

[0049] The blade group 14 has a plurality of blades 14a arranged along the circumferential direction B of the axis O. The radially outer ends of the plurality of blades 14a are provided on the radially inner peripheral surface of the outer peripheral side shroud 40 facing radially inward, and the radially inner ends are provided on the radially outer peripheral surface of the shroud section 43 facing radially outward.

[0050] In the present embodiment, the blade group 14 has five blades 14a, two end blades 41 are provided at both ends in the circumferential direction B of the shroud section 43, and three central blades 42 are provided in the center of the circumferential direction B of the shroud section 43 in a shape sandwiched between the two end blades 41.

[0051] The shroud section 43 connects the ends on the radially inner side of these multiple blades 14a so as to connect the multiple blades 14a of the blade group 14 in the circumferential direction B. Accordingly, the shroud section 43 restricts the circumferential movement of each blade 14a in the circumferential direction B.

[0052] The shroud section 43 is a structure that extends in the axial direction A and is formed in an arc shape centered on the axis O. A plurality of them are arranged in the circumferential direction B, and the ends of the respective shroud sections 43 are in contact with each other to form an annular inner peripheral side shroud. For the sake of facilitating the description of the present embodiment, Figure 2 one shroud section 43, one blade group 14 provided on the shroud section 43, and a part of the outer peripheral side shroud 40 are shown.

[0053] The pressing portion 44 is a leaf spring 50 provided so as to extend in the circumferential direction B between the blade group 14 and the shroud section 43.

[0054] Figure 3 (a) is Figure 2 an enlarged view of the IIIa portion of the end blade 41 shown, Figure 3 (b) is Figure 2 a cross-sectional view taken along the IIIb-IIIb line of the end blade 41 shown. And, Figure 3 (c) is Figure 2 an enlarged view of the IIIc portion of the central blade 42 shown, Figure 3 (d) is Figure 2 a cross-sectional view taken along the IIId-IIId line of the central blade 42 shown.

[0055] As shown in Figure 3 (b) and (d), the shroud section 43 has a recess 43a on the outer peripheral surface facing the radially outer side of the axis O that can accommodate the radially inner ends of the blades 14a. The recess 43a has an engaging portion 43b that extends in the axial direction A from the inner peripheral surface of the recess 43a. And, the radially inner ends of the respective blades 14a have a flange portion 14b that extends in the axial direction A. Thus, within the recess 43a, the flange portion 14b engages with the engaging portion 43b.

[0056] The leaf spring 50 contacts the radially inner peripheral surface of the blade 14a and applies an elastic pressure (acting force) toward the radially outer side to the blade 14a. Thus, a pressure for restraining the blade 14a with respect to the shroud section 43 is generated in the pressure generation region P defined by the engagement of the flange portion 14b and the engaging portion 43b. Thereby, the blade 14a is restrained from moving radially with respect to the shroud section 43.

[0057] Accordingly, the leaf spring 50 serving as the pressing portion 44 applies a pressure toward the radially outer side to the blade group 14, and thereby presses the blade group 14 against the shroud section 43 using the pressure generation region P.

[0058] The leaf spring thickness of the leaf spring 50 corresponding to each central vane 42 on the central side in the circumferential direction B of the shroud section 43 is formed to be thinner than the leaf spring thickness of the leaf spring 50 corresponding to the end vanes 41 at both ends in the circumferential direction B of the shroud section 43. Accordingly, the radially applied pressure generated in the pressure generation region P of the end vanes 41 becomes relatively stronger, and the radially applied pressure generated in the pressure generation region P of the central vanes 42 becomes relatively weaker. That is, the leaf spring 50 serving as the pressing portion 44 has a pressure distribution in which the pressure at the center in the circumferential direction B of the shroud section 43 is smaller than the pressure at both ends in the circumferential direction B of the shroud section 43.

[0059] (Function and effect)

[0060] The fixed vane ring 13 according to the first embodiment applies a pressure toward the radially outer side to the vane group 14 so that the leaf spring 50 serving as the pressing portion 44 presses the vane group 14 against the shroud section 43 via the pressure generation region P. Moreover, it is configured such that the radially applied pressure in the pressure generation region P is relatively stronger in the end vanes 41 and relatively weaker in the central vanes 42.

[0061] Accordingly, the end vanes 41 with a weaker binding force of the shroud section 43 can increase the natural frequency, and the central vanes 42 with a stronger binding force can decrease the natural frequency. Therefore, the natural frequencies of the respective vanes 14a are close to each other, and thus the frequency band of the natural frequency of the fixed vane ring 13 as a whole can be narrowed. As a result, it is easy to avoid the crossing of the excitation harmonics corresponding to the rotational speed during the operation of the gas turbine 1 and the frequency band of the natural frequency of the fixed vane ring 13 as a whole. As a result, resonance of the fixed vane ring 13 as a whole can be suppressed.

[0062] (Second embodiment)

[0063] Hereinafter, with reference to Figure 4 and Figure 5 the structure of the fixed vane ring 13 according to the second embodiment of the present invention will be described. In the second embodiment, the structure is the same as that of the first embodiment except for the structure of the pressing portion 44 included in the fixed vane ring 13. The same reference numerals are given to the constituent elements that are the same as those in the first embodiment, and the detailed description thereof is omitted. Figure 4 It is Figure 1 a cross-sectional view taken along the line II-II shown in

[0064] (Fixed vane ring)

[0065] The pressing portion 44 includes a crimping plate 70 and a plurality of bolts 60.

[0066] The crimping plate 70 is provided so as to extend in the circumferential direction B between the vane group 14 and the shroud section 43.

[0067] A plurality of bolts 60 are respectively disposed inside the shroud section 43 on the radially inner side of the crimping plate 70 in a manner corresponding to each blade 14a.

[0068] Figure 5 (a) is Figure 4 a cross-sectional view in the direction of the Va-Va line of the end blade 41 shown, Figure 5 (b) is Figure 4 a cross-sectional view in the direction of the Vb-Vb line of the central blade 42 shown.

[0069] As Figure 4 and Figure 5 shown in (a) and (b), one side 70a of the crimping plate 70 facing radially outward abuts against the radially inner peripheral surface of the blade 14a, and the other side 70b of the crimping plate 70 facing radially inward contacts the radially outer end of the bolt 60.

[0070] The plurality of bolts 60 press the crimping plate 70 respectively toward the radially outer side, thereby applying pressure to the blade group 14 via the crimping plate 70. Thus, a pressure for restraining the blade 14a with respect to the shroud section 43 is generated in the pressure generation region P, and the blade 14a is restrained so as not to move radially with respect to the shroud section 43.

[0071] Moreover, the tightening torque of the bolt 60 in the central blade 42 that contacts the crimping plate 70 is smaller than the tightening torque of the bolt 60 in the end blade 41 that contacts the crimping plate 70. Therefore, the radially applied pressure generated in the pressure generation region P of the end blade 41 becomes relatively stronger, and the radially applied pressure generated in the pressure generation region P of the central blade 42 becomes relatively weaker. That is, the pressing portion 44 has a pressure distribution in which the pressing force for pressing the blade 14a at the center of the circumferential direction B is smaller than the pressing force for pressing the blade 14a at both ends of the circumferential direction B.

[0072] (Function and effect)

[0073] The fixed blade ring 13 according to the second embodiment has the following structure: The crimping plate 70 and the plurality of bolts 60 as the pressing portion 44 apply a pressure toward the radially outer side to the blade group 14, and the radially applied pressure in the pressure generation region P of each blade 14a is relatively stronger in the end blade 41 and relatively weaker in the central blade 42.

[0074] Thus, the same function and effect as the structure of the first embodiment can be obtained. Moreover, the above function and effect can be achieved in a structure using simple and inexpensive materials such as the bolt 60 and the crimping plate 70.

[0075] (Third embodiment)

[0076] Hereinafter, with reference to Figure 6 and Figure 7The structure of the stationary vane ring 13 of the third embodiment of the present invention will be described. In the third embodiment, it has the same structure as the first embodiment except for the structure of the pressing portion 44 provided in the stationary vane ring 13. The same reference numerals are given to the constituent elements that are the same as those in the first embodiment, and the detailed description thereof is omitted. Figure 6 is Figure 1 a cross-sectional view taken along the line II-II shown in the figure.

[0077] (Stationary vane ring)

[0078] The pressing portion 44 has a crimping plate 70 and a plurality of actuators 90.

[0079] The crimping plate 70 is provided so as to extend circumferentially B between the vane group 14 and the shroud section 43.

[0080] The plurality of actuators 90 are respectively provided between the crimping plate 70 and the shroud section 43 in a manner corresponding to each vane 14a.

[0081] Figure 7 (a) is Figure 6 a cross-sectional view taken along the line VIIa-VIIa of the end vane 41 shown in the figure, Figure 7 (b) is Figure 6 a cross-sectional view taken along the line VIIb-VIIb of the central vane 42 shown in the figure.

[0082] The plurality of actuators 90 are respectively electrically connected to a power source (not shown) outside the stationary vane ring 13 through cables (not shown). The actuator 90 is a mechanical component that converts an electrical signal input from the power source into physical motion, and expands and contracts radially by a specified length corresponding to the voltage magnitude of the electrical signal when the electrical signal is input. The magnitude of the voltage of the electrical signal output from the power source is appropriately controlled from the outside of the gas turbine 1 by a computer (not shown). That is, the expansion and contraction amount of the actuator 90 corresponding to each vane 14a is appropriately controlled by the computer. For example, a piezoelectric element is used in the actuator 90.

[0083] The plurality of actuators 90 expand and contract toward the radially outer side and press the crimping plate 70, thereby applying pressure to the vane group 14 via the crimping plate 70. As a result, a pressure for restraining the vane 14a with respect to the shroud section 43 is generated in the pressure generation region P, and the vane 14a is restrained so as not to move radially with respect to the shroud section 43.

[0084] Moreover, the radial expansion and contraction amount of the actuator 90 in the central vane 42 that contacts the crimping plate 70 is smaller than that of the actuator 90 in the end vane 41 that contacts the crimping plate 70. Therefore, the pressing force of the actuator 90 applied radially in the pressure generation region P of the end vane 41 becomes relatively stronger, and the pressing force of the actuator 90 applied radially in the pressure generation region P of the central vane 42 becomes relatively weaker. As a result, the pressing portion 44 has a pressure distribution in which the pressing force for pressing the vane 14a at the center of the circumferential direction B is smaller than the pressing force for pressing the vane 14a at both ends of the circumferential direction B.

[0085] (Function and effect)

[0086] The fixed vane ring 13 according to the third embodiment has the following structure: The actuator 90 serving as the pressing portion 44 applies a pressure toward the radially outer side to the vane group 14, and the pressure applied radially in the pressure generation region P of each vane 14a is relatively stronger in the end vane 41 and relatively weaker in the central vane 42. Thus, the same function and effect as the structure of the first embodiment can be obtained.

[0087] Moreover, according to the above structure, the voltage of the electric signal input to the actuator 90 can be controlled by a computer. Thus, even during the operation of the gas turbine 1, the expansion and contraction amount of the actuator 90 can be controlled from the outside, and appropriate active control corresponding to the situation can be achieved. Therefore, the above function and effect can be improved.

[0088] (Other embodiments)

[0089] As described above, the embodiments of the present invention have been described in detail with reference to the accompanying drawings. However, the specific structure is not limited to the structures of the respective embodiments, and additions, omissions, replacements, and other changes can be made to the structure without departing from the gist of the present invention. Moreover, the present invention is not limited by the embodiments and is only limited by the claims.

[0090] In addition, the first modification of the second embodiment is shown in Figure 8 . As Figure 8 shown, it may be configured as follows: The bolts 60 of the pressing portion 44 are provided only corresponding to the end vanes 41 inside the shroud section 43 and are not provided in the central vane 42. That is, the pressing portion 44 applies a pressure toward the radially outer side to the vane group 14 by pressing only the vanes 14a at both ends of the circumferential direction B.

[0091] Thus, the pressure applied radially in the pressure generation region P of each vane 14a is relatively stronger in the end vane 41 and relatively weaker in the central vane 42, so that the same function and effect as the second embodiment can be obtained. Moreover, the portion where the bolts 60 are provided is limited to both ends of the circumferential direction B, so that the processing during manufacturing becomes easy.

[0092] Further, a plurality of bolts 60 may be provided corresponding to only the end blades 41.

[0093] Further, a second modification of the second embodiment is shown in Figure 9 . As Figure 9 shown, it may be configured such that a plurality of bolts 60 of two or more pressing portions 44 corresponding to the end blades 41 are provided inside the shroud section 43, and the number of bolts 60 pressing the central blade 42 is less than the number of bolts 60 pressing the end blades 41.

[0094] Accordingly, the pressure applied radially in the pressure generation region P of each blade 14a is relatively strong in the end blade 41 and relatively weak in the central blade 42, so that the same operational effects as those of the second embodiment can be obtained.

[0095] Further, a third modification of the second embodiment is shown in Figure 10 . As Figure 10 shown, it may be configured such that the pressing portion 44 further has a pressing spring 80 between the crimping plate 70 and the bolt 60.

[0096] Accordingly, the pressing force of the bolt 60 converted into elastic pressure (acting force) can be applied to the blade 14a. Therefore, when some abnormal vibration suddenly occurs in the stator 12 during the operation of the gas turbine 1, the impact force from the pressing portion 44 of the shroud section 43 is not applied to the blade 14a. Accordingly, an appropriate pressure can be generated through the pressure generation region P, thereby improving the reliability of the stationary blade ring 13.

[0097] Further, the structure of the pressing portion 44 included in the above-described embodiment is not limited to a structure that is separately independent, and the pressing portion 44 of the stationary blade ring 13 may be configured by appropriately combining them.

[0098] Further, the pressing portion 44 included in the stationary blade ring 13 of the above-described embodiment is disposed on the shroud section 43 side, but the pressing portion 44 may be disposed on the outer peripheral shroud 40 side. In this case, the pressing portion 44 applies a pressure toward the radially inner side to the blade group 14, and even in this case, the same operational effects as those of the above-described pressing portion 44 disposed on the shroud section 43 side are exhibited.

[0099] Further, the above-described pressing portion 44 may be disposed on both the outer peripheral shroud 40 side and the shroud section 43 side. Accordingly, the above-described operational effects can be further improved.

[0100] Further, the pressing portion 44 is not limited to the structure of the leaf spring 50 described in the first embodiment above. For example, as Figure 11As shown, the pressing portion 44 is a leaf spring 51 that is provided to extend in the circumferential direction B between the blade group 14 and the shroud section 43. The leaf spring 51 may have a pair of flat portions 51a disposed at both ends in the circumferential direction B in the shroud section 43 and a corrugated portion 51b disposed between the flat portions 51a at both ends in the circumferential direction B. Hereinafter, the structures of the flat portion 51a and the corrugated portion 51b of the leaf spring 51 when the pressing portion 44 is the leaf spring 51 will be described.

[0101] The flat portion 51a is in a flat plate shape. When viewed from the axial direction A, the flat portion 51a extends linearly. One end in the circumferential direction B of the flat portion 51a disposed on one side in the circumferential direction B among the pair of flat portions 51a is fixed to the end in the circumferential direction B on one side in the shroud section 43. The other end in the circumferential direction B of this flat portion 51a is located at a position more radially outward than this one end.

[0102] One end in the circumferential direction B of the flat portion 51a disposed on the other side in the circumferential direction B among the pair of flat portions 51a is fixed to the end in the circumferential direction B on the other side in the shroud section 43. The one end in the circumferential direction B of this flat portion 51a is located at a position more radially outward than this other end.

[0103] The corrugated portion 51b is in a corrugated plate shape extending in the circumferential direction B. When viewed from the axial direction A, the corrugated portion 51b extends in a curved shape. Specifically, when viewed from the axial direction A, the corrugated portion 51b undulates in the circumferential direction B. Both ends in the circumferential direction B of the corrugated portion 51b are respectively connected to the ends of the pair of flat portions 51a. Therefore, the corrugated portion 51b is clamped by the flat portions 51a at both ends in the circumferential direction B.

[0104] The thickness of the corrugated portion 51b is the same as the thickness of the flat portion 51a. In addition, the same thickness mentioned here means substantially the same thickness, allowing for slight manufacturing errors or design tolerances.

[0105] Here, the connecting portion between the flat portion 51a and the corrugated portion 51b is in a region of the shroud section 43 that is more radially inward than the blade 14a in the blade group 14 and is located at a position more on both ends in the circumferential direction B than the central blade 42.

[0106] Therefore, the leaf spring 51 corresponding to each central blade 42 provided on the central side in the circumferential direction B of the shroud section 43 is the corrugated portion 51b, and the leaf spring 51 corresponding to the end blades 41 provided at both ends in the circumferential direction B is the flat portion 51a. According to this structure, the same effects as those described in the above first embodiment can also be achieved.

[0107] Moreover, the stationary vane ring 13 in the above embodiment is the stationary vane ring 13 used in the gas turbine 1, but it can also be used in other rotating machines such as steam turbines.

[0108] [Supplementary Note]

[0109] The fixed blade ring 13 and the rotary machine described in the embodiments can be understood as follows.

[0110] (1) The fixed blade ring 13 according to the first embodiment includes: a blade group 14 having a plurality of blades 14a arranged in the circumferential direction B of the axis O; a shroud section 43 connecting the radial ends of these plurality of blades 14a so as to connect the plurality of blades 14a of the blade group 14 in the circumferential direction B and having an arc shape extending in the circumferential direction B; and a pressing portion 44 applying pressure to the blade group 14 in the radial direction so that the blade group 14 is pressed against the shroud section 43, and the pressing portion 44 has a pressure distribution in which the pressure at the center in the circumferential direction B of the shroud section 43 is smaller than the pressure at both ends in the circumferential direction B of the shroud section 43.

[0111] Thereby, the natural frequency of the end blades 41 can be increased, and thus the natural frequency generated in the central blade 42 can be decreased. Therefore, the natural frequencies of the respective blades 14a are close to each other, and thus the frequency band of the natural frequency of the fixed blade ring 13 as a whole can be narrowed.

[0112] (2) The fixed blade ring 13 according to the second embodiment is the fixed blade ring 13 of (1), and it may be as follows: the pressing portion 44 has a leaf spring 50 provided to extend in the circumferential direction B between the blade group 14 and the shroud section 43 and apply the pressure, and the thickness of the leaf spring 50 at the center in the circumferential direction B of the shroud section 43 is thinner than the thickness at both ends in the circumferential direction B of the shroud section 43.

[0113] Thereby, an appropriate pressure can be applied to the blade group 14 by a more specific method, and thus the natural frequency of the central blade 42 can be decreased and the natural frequency of the end blades 41 can be increased.

[0114] (3) The fixed blade ring 13 according to the third embodiment is the fixed blade ring 13 of (1), and it may be as follows: the pressing portion 44 has a plurality of bolts 60 applying the pressure by pressing each of the blades 14a of the blade group 14 in the radial direction, and the pressing force of the bolts 60 pressing the blades 14a at the center in the circumferential direction B of the shroud section 43 is smaller than the pressing force of the bolts 60 pressing the blades 14a at both ends in the circumferential direction B of the shroud section 43.

[0115] Thereby, pressure can be applied to the blade group 14 by a simple and inexpensive structure such as the bolts 60, and thus the natural frequency of the central blade 42 can be decreased and the natural frequency of the end blades 41 can be increased.

[0116] (4) The stationary vane ring 13 according to the fourth mode is the stationary vane ring 13 of (1), and it may be as follows: The pressing portion 44 has a plurality of bolts 60 that apply the pressure by pressing only the vanes 14a at both ends in the circumferential direction B of the shroud section 43.

[0117] Thus, it is possible to apply pressure to the vane group 14 through a simple and inexpensive structure such as the bolts 60, so that the natural frequency of the central vane 42 can be reduced and the natural frequency of the end vane 41 can be increased. Moreover, since the positions where the bolts 60 are provided are limited to both ends in the circumferential direction B, the machining during manufacturing becomes easy.

[0118] (5) The stationary vane ring 13 according to the fifth mode is the stationary vane ring 13 of (1), and it may be as follows: The pressing portion 44 has a plurality of bolts 60 that apply the pressure by pressing each of the vanes 14a of the vane group 14 in the radial direction, and the number of the bolts 60 pressing the vanes 14a at the center in the circumferential direction B of the shroud section 43 is smaller than the number of the bolts 60 pressing the vanes 14a at both ends in the circumferential direction B of the shroud section 43.

[0119] Thus, it is possible to apply pressure to the vane group 14 through a simple and inexpensive structure such as the bolts 60, so that the natural frequency of the central vane 42 can be reduced and the natural frequency of the end vane 41 can be increased.

[0120] (6) The stationary vane ring 13 according to the sixth mode is any one of the stationary vane rings 13 in (3) to (5), and it may be as follows: The pressing portion 44 further has a crimping plate 70 extending in the circumferential direction B between the vane group 14 and the pressing portion 44, and the bolts 60 press the vanes 14a via the crimping plate 70.

[0121] Thus, the vane group 14 is pressed in a surface manner by the crimping plate 70, so that pressure can be applied to the vane group 14 more effectively.

[0122] (7) The stationary vane ring 13 according to the seventh mode is the stationary vane ring 13 of (6), and it may be as follows: The pressing portion 44 further has a crimping spring 80 provided between the crimping plate 70 and the bolts 60.

[0123] Thus, by interposing the crimping spring 80, the vane group 14 can be pressed more appropriately by the elastic pressure.

[0124] (8) The stationary vane ring 13 according to the eighth mode is the stationary vane ring 13 of (1), and it may be as follows: The pressing portion 44 has a plurality of actuators 90 that apply the pressure by pressing each of the vanes 14a of the vane group 14 in the radial direction, and a crimping plate 70 that extends in the circumferential direction B between the vane group 14 and the actuator 90. Compared with the pressing force of the actuator 90 that presses the vanes 14a at both ends in the circumferential direction B in the shroud section 43 via the crimping plate 70, the pressing force of the actuator 90 that presses the vanes 14a at the center in the circumferential direction B in the shroud section 43 via the crimping plate 70 is smaller.

[0125] Thus, during the operation of the gas turbine 1, the expansion and contraction amount of the actuator 90 can also be controlled, so that appropriate active control corresponding to the situation can be achieved.

[0126] (9) The stationary vane ring 13 according to the ninth mode is the stationary vane ring 13 of (1), and it may be as follows: The pressing portion 44 has a leaf spring 51 that is provided to extend in the circumferential direction B between the vane group 14 and the shroud section 43 and applies the pressure. The leaf spring 51 has flat plate portions 51a disposed at both ends in the circumferential direction B in the shroud section 43 and a corrugated plate portion 51b disposed between the flat plate portions 51a at both ends in the circumferential direction B.

[0127] Thus, an appropriate pressure can be applied to the vane group 14 by a more specific method, so that the natural frequency of the central vane 42 can be reduced and the natural frequency of the end vane 41 can be increased.

[0128] (10) The rotary machine according to the tenth mode includes any one of the stationary vane rings 13 in (1) to (9).

[0129] Thus, a rotary machine with a narrowed frequency band of the natural frequency in the stationary vane ring 13 can be provided.

[0130] Industrial Applicability

[0131] According to the present invention, a stationary vane ring and a rotary machine capable of narrowing the frequency band of the natural frequency can be provided.

[0132] Symbol Description

[0133] 1 - Gas turbine, 2 - Compressor, 3 - Compressor rotor, 4 - Compressor housing, 5 - Compressor rotating blade ring, 7 - Compressor stationary blade ring, 9 - Burner, 10 - Turbine, 11 - Rotor, 11a - Rotating shaft, 12 - Stator, 13 - Stationary blade ring, 14 - Blade group, 14a - Blade, 14b - Flange portion, 15 - Turbine housing, 20 - Turbine rotating blade ring, 40 - Outer peripheral side shroud, 41 - End blade, 42 - Central blade, 43 - Shroud section, 43a - Recess, 43b - Engaging portion, 44 - Pressing portion, 50, 51 - Leaf spring, 51a - Flat plate portion, 51b - Corrugated plate portion, 60 - Bolt, 70 - Crimping plate, 70a - One side, 70b - The other side, 80 - Crimping spring, 90 - Actuator, O - Axis, A - Axial direction, B - Circumferential direction, P - Pressure generating region.

Claims

1. A stationary vane ring, comprising: A vane group having a plurality of vanes arranged circumferentially along an axis; A shroud section connecting radial ends of these plurality of vanes so as to connect the plurality of vanes of the vane group along the circumferential direction and having an arc shape extending along the circumferential direction; And A pressing portion applying pressure to the vane group in the radial direction so that the vane group is pressed against the shroud section, The pressing portion has a pressure distribution in which the pressure at the circumferential center in the shroud section is smaller than the pressures at the circumferential both ends in the shroud section.

2. The stationary vane ring according to claim 1, wherein The pressing portion has a leaf spring provided to extend along the circumferential direction between the vane group and the shroud section and applying the pressure, The leaf spring has a plate thickness at the circumferential center in the shroud section thinner than the plate thicknesses at the circumferential both ends in the shroud section.

3. The stationary vane ring according to claim 1, wherein The pressing portion has a plurality of bolts applying the pressure by pressing each of the vanes of the vane group in the radial direction, Compared with the pressing force of the bolts pressing the vanes at the circumferential both ends in the shroud section, the pressing force of the bolts pressing the vanes at the circumferential center in the shroud section is smaller.

4. The stationary vane ring according to claim 1, wherein The pressing portion has a plurality of bolts applying the pressure by pressing only the vanes at the circumferential both ends in the shroud section.

5. The stationary vane ring according to claim 1, wherein The pressing portion has a plurality of bolts applying the pressure by pressing each of the vanes of the vane group in the radial direction, Compared with the number of the bolts pressing the vanes at the circumferential both ends in the shroud section, the number of the bolts pressing the vanes at the circumferential center in the shroud section is smaller.

6. The stationary vane ring according to any one of claims 3 to 5, wherein The pressing portion further has a crimping plate extending along the circumferential direction between the vane group and the pressing portion, The bolts press the vanes via the crimping plate.

7. The stationary vane ring according to claim 6, wherein The pressing portion further has a crimping spring provided between the crimping plate and the bolts.

8. The stationary vane ring according to claim 1, wherein The pressing portion has: A plurality of actuators applying the pressure by pressing each of the vanes of the vane group in the radial direction; And A crimping plate extending along the circumferential direction between the vane group and the actuators, Compared with the pressing force of the actuators pressing the vanes at the circumferential both ends in the shroud section via the crimping plate, the pressing force of the actuators pressing the vanes at the circumferential center in the shroud section via the crimping plate is smaller.

9. The stationary vane ring according to claim 1, wherein The pressing portion has a leaf spring provided to extend along the circumferential direction between the vane group and the shroud section and applying the pressure, The leaf spring has: A flat plate portion disposed at the circumferential both ends in the shroud section; and A corrugated plate portion disposed between the flat plate portions at the circumferential both ends.

10. A rotary machine, comprising the stationary blade ring according to any one of claims 1 to 9.

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