JP2009002338A - Stationary blade ring, axial flow compressor using the same, and method for repairing stationary blade ring - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stationary blade ring, capable of restricting risk of thermal deformation and strength deterioration, securing a degree of freedom regarding the shape, and improving compression performance. <P>SOLUTION: The stationary blade ring is provided with a stationary blade member 21, having an inner shroud part 31 and an outside shroud part 29 integrally formed with both end parts of a stationary blade 27 as parted to correspond to each piece of the stationary blade 27, and a coupling member 23, formed of an arc-shaped plate member, and installed on the opposite side to a plurality of stationary blades 27 on at least either the inner shroud part 31 or the outer shroud part 29 of the stationary member 21 adjoining each other in the circumferential direction. The stationary blade member 21 is welded with the coupling member 23 in part of its circumferential length to form a stationary blade ring segment 19. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an axial flow compressor such as a gas turbine compressor, and more particularly to a stationary blade ring of an axial flow compressor and a repair method thereof.

The stationary blade ring of the axial flow compressor has a large number of, for example, several tens to several hundreds of stationary blades arranged at substantially equal intervals in the circumferential direction.
Conventionally, as shown in Patent Document 1 and Patent Document 2, for example, the stationary blade ring is assembled by inserting both ends of the stationary blade into the inner and outer shroud holes forming the casing wall. After that, a method in which electron beam welding is performed circumferentially from the side surface of the shroud and the stationary blade and the inner and outer shrouds are joined is often used.

In addition, the stationary blades of the axial compressor may be damaged because they are subjected to high stress due to mechanical, thermal and rotational stress factors.
As a method for repairing this damage, for example, as shown in Patent Document 3, a damaged portion is scraped off, and a repair member having substantially the same shape as the shaved portion is fitted and brazed and joined. .
Further, as shown in Patent Document 4, a proposal has been proposed in which a stationary blade and a shroud are fitted to each other and coupled with a bolt to facilitate replacement of a damaged stationary blade.

Japanese Patent Publication No. 58-57276 Japanese Patent Publication No.59-2761 JP 2002-303155 A JP-A-10-205305

However, in the ones disclosed in Patent Document 1 and Patent Document 2, since the electron beam welding is performed so that the joint portion extends from the side surface of the shroud to the central portion of the stationary blade over the entire circumference of the stationary blade ring. A large amount of heat acts on the shroud. This amount of heat may cause deformation of the stationary blade and the shroud.
When the stationary blade is distorted, the air flow is disturbed and the compression efficiency is lowered. Further, when the shroud is distorted, for example, the inner surface of the shroud undulates, so that the shroud protrudes or retracts into the vehicle interior. For this reason, a level | step difference is made between the casing inner surface and shroud inner surface of a vehicle interior, and since the flow in a vehicle interior is disturb | confused, compression performance falls.

As shown in Patent Document 3, in the case where the blade is partially repaired, the reliability of brazing or welding is low, and there is a risk that the cost may be increased by increasing the repair frequency. For this reason, it is not actually used, and the current situation is that the stator blade ring is replaced with a new one.
Since the number of parts shown in Patent Document 4 is large, the inspection at the regular inspection took time. In addition, the bolt joint may be loosened due to vibration during operation.

The present invention has been made in view of the above circumstances, and suppresses the fear of thermal deformation and strength reduction, ensures a degree of freedom in shape, and improves compression performance, and axial flow compression using the same The purpose is to provide a machine.
It is another object of the present invention to provide a method for repairing a stator blade ring that is highly reliable and can be repaired at low cost in a short time.

The present invention employs the following means in order to solve the above problems.
According to a first aspect of the present invention, a stator blade divided body in which an inner shroud portion and an outer shroud portion divided so as to correspond to one stator blade are integrally formed at both ends of the stator blade, and an arc shape is provided. And a coupling member that is installed on the opposite side to the stationary blade of at least one of the inner shroud portion and the outer shroud portion of the plurality of stationary blade divided bodies adjacent to each other in the circumferential direction. The stator blade divided body provides a stator blade ring in which a part of the circumferential length is welded to the coupling member to form a stator blade ring segment.

According to this aspect, the stator blade divided body formed integrally is positioned at a predetermined position of the coupling member, and a part of the circumferential length of the stator blade divided body is welded to the coupling member and fixed. By repeating this for each stator blade divided body, a stator blade ring segment which is a portion of an arcuate stator blade ring is formed.
A ring-shaped stator blade ring is formed by sequentially inserting the stator blade ring segment into a guide groove provided in the casing with a fitting portion provided on a side portion of the outer shroud portion.

Thus, since a part of circumferential length of the stationary blade divided body is welded to the coupling member, the amount of heat input can be reduced. And since a stationary blade division | segmentation body is welded one by one and it is discontinuous, heat can be dissipated in air and there is little fear of accumulation. Further, since the stationary blade divided body is joined on the side opposite to the stationary blade in the inner or outer shroud portion, heat hardly affects the stationary blade.
Therefore, the possibility that the formed stator blade ring segment is deformed by heat can be suppressed. Thereby, since the flow of compressed gas is prevented from being disturbed due to thermal deformation, predetermined compression performance can be maintained.
Moreover, since the stator blade divided body and the coupling member are joined by welding, the joining strength is strong and sufficient structural strength can be maintained.
Furthermore, since the shape of the stationary blade is irrelevant to the joining of the stationary blade divided body and the coupling member, the shape of the stationary blade can be freely determined in accordance with the required compression performance.

Moreover, in the said aspect, it is suitable for the inner shroud part in which the said joining member is installed, or the said outer shroud part is equipped with the groove part in which the said joining member is inserted.
If it does in this way, positioning in the direction which intersects the peripheral direction to the connecting member of a stationary blade division object can be performed easily and correctly.

Moreover, in the said aspect, the surface on the opposite side with respect to the said stationary blade of the said joining member is rather than the surface on the opposite side with respect to the said stationary blade of the inner shroud part in which the said joining member is installed, or the said outer shroud part. It is preferable to be located on the stationary blade side.
In this case, even if the coupling member is deformed by thermal stress, it does not protrude outward from the inner shroud part or the outer shroud part. For example, when inserting the stationary blade ring segment into the guide groove of the casing, The member does not contact the guide groove. Accordingly, since the sliding area between the stator blade ring segment and the guide groove can be reduced, the assembly operation of the stator blade ring can be easily performed.

  According to the second aspect of the present invention, there is provided an axial compressor provided with a stationary blade ring capable of suppressing the fear of thermal deformation and strength reduction, ensuring the degree of freedom of shape, and improving the compression performance.

According to this aspect, the strength and compression performance of the axial flow compressor are improved because the stator blade ring that suppresses the fear of thermal deformation and strength reduction, ensures the degree of freedom of shape, and improves the compression performance is provided. Can be made.
Thereby, for example, the thermal efficiency of the gas turbine can be improved.

  According to a third aspect of the present invention, there is provided a method for repairing a stator blade ring as described above, wherein the welded portion of the stator blade segment damaged in the stator blade ring segment is welded from the stator blade segment side. A separation step of separating the stationary blade divided body and the coupling member, removing the separated stationary blade divided body, and forming the newly formed stationary blade divided body into the stationary blade ring segment. Provided is a method for repairing a stator blade ring, which includes a fitting step for fitting, and a joining step for joining the newly formed stator blade divided body and the coupling member by welding.

According to this aspect, a vane ring segment having a vane segment that is damaged, in other words, that requires repair, is removed. The damaged stator blade segment of the stator blade ring segment is scraped off from the stator blade segment in the separation step and separated from the coupling member. Then, the stator blade divided body damaged in the replacement process is removed, and the newly formed stator blade divided body is fitted. In the joining process, the fitted stator blade divided body is repaired by being joined to the coupling member by welding.
Thus, since the damaged stator blade divided body is replaced with a new stator blade divided body, the reliability can be improved. Further, since the stationary blade divided body is joined to the coupling member by welding, the joined portion is not loosened by vibration during operation. Thereby, the reliability of the stationary blade ring can be increased.
Further, since only the damaged stator blade divided body is replaced, the working time is shortened and the cost can be reduced as compared with the replacement of the stator blade ring or the entire stator blade ring segment.

In the above aspect, it is preferable that, in the separation step, the surface of the coupling member is scraped off so that a melted portion accompanying welding becomes a predetermined ratio or less.
If it does in this way, the reliability of joining by welding with a new stator blade division body and a coupling member can be improved.

According to the stator blade ring of the present invention, the integrally formed stator blade divided body is positioned at a predetermined position of the coupling member, and a part of the circumferential length of the stator blade divided body is fixed to the coupling member by welding, Since the arc-shaped stator blade ring segment is formed, the possibility that the formed stator blade ring is deformed by heat can be suppressed and sufficient structural strength can be maintained.
In addition, the flow of compressed gas is prevented from being disturbed due to thermal deformation, and the shape of the stationary blade can be freely determined according to the required compression performance, so that the predetermined compression performance is maintained. be able to.
Moreover, according to the stator blade ring repair method of the present invention, the reliability of the stator blade ring can be increased, the working time can be shortened, and the cost can be reduced.

Hereinafter, a gas turbine according to an embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a schematic cross-sectional view showing an upper half portion of a gas turbine 1 according to the present embodiment. FIG. 2 is a side view showing the stationary blade ring 13 according to the present embodiment. FIG. 3 is a perspective view showing the stator blade ring segment 19 according to the present embodiment. 4 is a cross-sectional view taken along line XX in FIG. FIG. 5 is a partial plan view of the stationary blade ring segment 19 as viewed from the outside.

  As shown in FIG. 1, a gas turbine 1 includes a compressor (axial compressor) 3 that compresses air, a combustor 5 that combusts fuel using the air compressed by the compressor 3, and a combustor 5. And a turbine 7 to which the combustion gas from is introduced. The equipment constituting the gas turbine 1 including the compressor 3, the combustor 5 and the turbine 7 is covered with a casing 9.

The compressor 3 is an axial compressor in which the moving blade rings 11 and the stationary blade rings 13 are alternately provided in the rotation axis direction.
The moving blade ring 11 is constituted by a large number of moving blades 17 attached radially around the rotating shaft 15. A large number of moving blades 17 are installed along the circumferential direction P at substantially equal intervals.
As shown in FIG. 2, the stator blade ring 13 includes eight stator blade ring segments 19 divided in the circumferential direction P.

As shown in FIG. 3, the stationary blade ring segment 19 includes a plurality of stationary blade bodies (stator blade divided bodies) 21, a coupling member 23 that couples the stationary blade bodies 21, and a seal holder 25. .
The stationary blade body 21 includes a stationary blade 27, an outer shroud portion 29 divided so as to correspond to one of the stationary blades 27, and an inner shroud portion 31 divided so as to correspond to one of the stationary blades 27. And.

In the stationary blade body 21, the stationary blade 27, the outer shroud portion 29, and the inner shroud portion 31 are integrally formed by cutting out from a 13Cr stainless steel block.
The outer shroud portion 29 has a substantially rectangular parallelepiped shape. The outer shroud portion 29 is provided with projections 33 at the outer ends of both ends in the rotation axis direction R over the entire length in the circumferential direction P.
A guide groove portion 35 for slidably guiding the outer shroud portion 29 is provided on the inner peripheral surface of the casing 9. The protrusions 33 are fitted into recesses provided at both ends of the guide groove 35 in the rotation axis direction R, and have a function of guiding the sliding of the outer shroud 29.

  A groove 39 is provided on the outer surface 37 of the outer shroud portion 29 (the surface on the side opposite to the stationary blade 27) over the entire length in the circumferential direction P at a substantially central portion in the rotational axis direction R thereof. The bottom surface of the groove 39 is a circular arc whose cross-sectional shape along the circumferential direction P is convex outward. Both end portions in the rotation axis direction R of the groove 39 are inclined surfaces opened outward.

The inner shroud portion 31 has a substantially rectangular parallelepiped shape. The outer surfaces of both end portions in the rotation axis direction R of the inner shroud portion 31 are formed in a U shape in which a cross section along the rotation axis direction R is opened toward the rotation axis direction R outside.
A groove 43 is provided in the inner side surface (surface opposite to the stationary blade 27) 41 of the inner shroud portion 31 in the substantially central portion in the rotation axis direction R over the entire circumferential direction P.

The coupling member 23 is, for example, a long plate made of 13Cr stainless steel. The coupling member 23 is bent so that the surface portion has an arc shape. The connecting member 23 has a length corresponding to approximately one eighth of the stationary blade ring 1.
The cross-sectional shape of the coupling member 23 is a trapezoid, and its long side portion is substantially equal to the length of the inner surface of the groove 39 in the rotation axis direction R. The thickness of the coupling member 23 is smaller than the depth of the groove 39.

When the long side portion of the coupling member 23 is disposed on the bottom surface of the groove 39, the side surface of the coupling member 23 and the side surface of the groove 39 form a substantially V-shaped groove.
The stationary blade body 21 is coupled to the coupling member 23 by TIG welding, with the groove 39 of the outer shroud portion 29 fitted into the coupling member 23. As shown in FIG. 5, the welded portion 45 is approximately one third (a part) of the circumferential length of the outer shroud portion 29.
Welding is not limited to TIG welding, and for example, an appropriate one such as electron beam welding may be used.

Both end portions in the rotation axis direction R of the groove 39 are inclined surfaces that are open to the outside. This is, for example, substantially orthogonal to the bottom surface as shown in FIGS. 11 and 12. It may be a surface, or may be stepped as shown in FIG.
In this case, the cross-sectional shape and the width of the coupling member 23 are appropriately selected according to the shape of the groove 39.

For example, the connecting member 23 shown in FIG. 11 has a substantially rectangular cross-sectional shape and a width substantially equal to the width of the groove 39.
In this case, the coupling member 23 and the outer shroud portion 29 are joined by fillet welding.
When the width of the coupling member 23 is substantially equal to the width of the groove 39, the coupling member 23 can be easily positioned in the rotation axis direction R.

The connecting member 23 shown in FIG. 12 has a substantially rectangular cross-sectional shape and a width smaller than the width of the groove 39.
In this case, since welding can be performed so as to flow into the gap between the side surface of the groove 39 and the coupling member 23, the welding operation is facilitated.

The coupling member 23 shown in FIG. 13 has a substantially rectangular cross-sectional shape and a width substantially equal to the width on the bottom side of the groove 39.
In this case, the coupling member 23 can be easily positioned in the rotational axis direction R on the bottom side surface of the groove 39, and welding can be easily performed by pouring into the gap between the upper side surface of the groove 39 and the coupling member 23.

The seal holder 25 has a length corresponding to approximately one eighth of the stationary blade ring 1. Protrusions 47 are provided at upper portions on both sides in the rotational axis direction R of the seal holder 25 so as to be fitted to U-shaped side surfaces that are open toward the outside in the rotational axis direction R of the inner shroud portion 31. .
A seal member 49 is attached to the lower part of the seal holder 25.
The seal holder 25 communicates with and engages with all the inner shroud portions 31 constituting the stationary blade ring segment 19 and has a function of holding the position of the inner shroud portion 31.

The combustor 5 is connected to the compressor 3 by a compressed air supply passage 51. A plurality of combustors 5 are provided in the circumferential direction, and the compressed air supplied through the compressed air supply passage 51 and the separately supplied fuel are mixed and burned to generate high-temperature and high-pressure combustion gas, which is supplied to the turbine 7. Supply.
The turbine 7 is an axial turbine in which stationary blades and moving blades are alternately provided in the rotation axis direction R. The rotor blades are attached to the rotating shaft 15 and moved in the rotating direction by the high-temperature and high-pressure combustion gas to rotate the rotating shaft 15.
The rotary shaft 15 rotates the rotor blade ring 11 of the compressor 3 and is connected to, for example, a generator (not shown) to generate electric power.

The assembly and assembly of the stationary blade ring 13 configured as described above will be described.
First, a predetermined number of stator blades 21, coupling members 23, and seal holders 25 each having a predetermined shape are manufactured.
The stationary blade body 21 is machined into a predetermined shape by cutting out from the material block.
The coupling member 23 cuts a long plate material into a predetermined length and width, and processes (cuts and cuts) inclined surfaces on both sides. Thereafter, bending is performed so as to form an arc having a predetermined radius of curvature.

One stationary blade body 21 is brought into one end of the coupling member 23. Since a mark indicating the installation position of the outer shroud portion 29 is provided in advance at the end of the coupling member 23, the groove 39 of the outer shroud portion 29 is installed so as to fit the coupling member 23 in accordance with this mark. To do.
As described above, since the positioning of the stationary blade body 21 with respect to the coupling member 23 in the rotation axis direction R can be performed by fitting the groove 39 to the coupling member 23, it can be easily and accurately performed.
TIG welding is applied to the V-shaped groove formed by the groove 39 and the coupling member 23, and both are joined. As shown in FIG. 5, the TIG welding is performed at a substantially central position in the circumferential direction P over the length of approximately one third of the outer shroud portion 29.

Next, the second stationary blade body 21 is brought in. At this time, the second outer shroud portion 29 is positioned with the other end side end face of the outer shroud portion 29 of the stationary vane body 21 already joined as a mark (for example, abutting).
In this state, the second stationary blade body 21 is joined to the coupling member 23 by TIG welding as described above.
By repeating this, a predetermined number of stationary blade bodies 21 are joined to the coupling member 23.
Although the outer shroud portion 29 is used as a positioning mark for the second and subsequent pieces, for example, a separate mark may be provided on the coupling member 23, or the position may be measured and positioned each time.

After all the stationary blade bodies 21 are joined to the coupling member 23, the seal holder 25 is attached to the inner shroud portion 31 of the stationary blade body 21.
The seal holder 25 is inserted from the end of the inner shroud portion 31 on one end side so that the projection 47 is fitted to the side surface of the inner shroud portion 31.
In this way, the stator blade ring segment 19 is formed.

The protrusions 33 provided on both sides of each outer shroud portion 29 form a substantially continuous arc shape.
The manufactured stator blade ring segment 19 is brought into the casing 9. The protrusion 33 of the stator blade ring segment 19 is fitted into the recess of the guide groove portion 35 provided in the casing 9, and the stator blade ring segment 19 is slid along the guide groove portion 35 and installed at a predetermined position.
This is sequentially repeated to assemble the stationary blade ring 13.

In this way, the outer shroud portion 29 of the stationary blade body 21 has only a small third of the circumferential direction P length welded to the coupling member 23, and therefore the amount of heat input to the stationary blade body 21 is small.
And the stationary blade body 21 is welded one by one, and since it is discontinuous, the heat accompanying welding can be dissipated in the air and there is little possibility of accumulation.
Further, since the stationary blade body 21 is joined to the coupling member 23 at the groove 39 on the opposite side to the stationary blade 27 of the outer shroud portion 29, heat from welding affects the stationary blade 27. Less is.

Therefore, the possibility that the formed stator blade ring segment is deformed by heat can be suppressed.
Thereby, since the entrance / exit of the outer shroud part 29 to / from the air passage and the deformation of the stationary blade 27 are suppressed, it is possible to suppress the disturbance of the flow of the compressed air.
Thereby, since the compressor 3 can hold | maintain predetermined compression performance, the thermal efficiency of the gas turbine 1 can be improved.

Further, since the stationary blade body 21 and the coupling member 23 are joined by welding and the joining strength is strong, the stationary blade ring 13 can maintain a sufficient structural strength.
Furthermore, since the shape of the stationary blade 27 is irrelevant to the joining of the stationary blade body 21 and the coupling member 23, the shape of the stationary blade 27 can be freely determined according to the required compression performance.

Since the thickness of the coupling member 23 is smaller than the depth of the groove 39, the outer surface of the coupling member 23 is located on the inner side (the stationary blade 27 side) than the outer surface 37 of the outer shroud portion 29.
For this reason, even if the coupling member 23 is deformed by thermal stress, the coupling member 23 does not protrude outward from the outer shroud portion 29. For example, when the stationary blade ring segment 19 is inserted into the guide groove 35 of the casing 9, the coupling member 23 Does not contact the guide groove 35. Therefore, since the sliding area between the stationary blade ring segment 19 and the guide groove 39 can be reduced, the assembly operation of the stationary blade ring 13 can be easily performed.

During operation of the gas turbine 1, the stationary blades 27 of the stationary blade ring 13 are vibrated by the air flow. In the present embodiment, the friction damping effect is generated when the contact portion between the adjacent inner shroud portions 31 or between the inner shroud portion 31 and the seal holder 25 slides. be able to.
Thereby, since the stress acting on the stationary blade 27 can be reduced, the stationary blade 27 can be thinned and the performance of the compressor can be improved.

Next, for example, repair when one of the stationary blades 27 is damaged will be described with reference to FIGS.
First, the turbine 7 and the stationary blade ring 13 are disassembled and damaged, in other words, the stationary blade ring segment 19 having the stationary blade body 21 that requires repair is taken out (extraction step). The stator blade ring segment 19 is in the state shown in FIG.
Next, a separation step for separating the damaged stationary blade body 21 from the stationary blade ring segment 19, in other words, the coupling member 23 is entered.

As shown in FIG. 6, the welded portions 45 on both sides of the coupling member 23 are sequentially scraped off from the projection 33 of the outer shroud portion 29 to the welded portion 45 by, for example, a grinder. At this time, the grinder is sharpened with rough eyes, but care is taken not to damage the joining member 23.
When the weld 45 is scraped off, the stationary blade body 21 and the coupling member 23 are separated as shown in FIG.

In this state, as shown in FIG. 8, the fusion part 53 associated with the previous welding exists on the surface of the coupling member 23, and therefore, for example, the fusion part 53 is carefully scraped by a fine grinder. Avoid impact.
As a guideline, for example, the area of the melting portion 53 is less than 50%, in other words, the area of the base of the joining member 23 is 50% or more. The connecting member 23 is cut down to the line 55 that becomes like this.

Thus, when the area of the base of the joining member 23 is 50% or more, the reliability of joining by welding a new stationary blade body 22 and a coupling member 23 described later can be improved.
When the area of the base of the joining member 23 is cut to a position where the base of the joining member 23 becomes 100% as indicated by a line 57, the welding state becomes the same as the initial state. Absent.
It is an example that the area of this base is 50% or more, and it may be appropriately set as long as the next welding is performed satisfactorily.

  The outer shroud 29 has only about one third of the length in the circumferential direction P welded to the coupling member 23, so that a portion that is not welded to the corresponding coupling member 23 has a circumference in the outer shroud 29. About two thirds of the direction P length remains. When the next welding is performed using this portion, it is not necessary to remove the melted portion 53. Further, if a part of this part is used, the ratio of the area of the base may be reduced.

Next, the exchange process is started.
That is, the seal holder 25 engaged with the inner shroud portion 31 of the stationary blade body 21 is removed. If it carries out like this, since the stationary blade body 21 in an inner side will be isolate | separated separately, the stationary blade body 21 separated from the coupling member 23 can move freely.
When this stationary blade body 21 is removed, the stationary blade body 21 welded to the coupling member 23 remains as it is, and the removed portion of the stationary blade body 21 becomes a space.
As shown in FIG. 9, the newly formed stationary blade body 22 is brought into this space and installed so that the groove 39 of the outer shroud portion 29 is fitted to the coupling member 23.

The seal holder 25 is attached so as to be fitted to the inner shroud portions 31 of all the stationary blade bodies 21 and 22.
After finely adjusting the position of the new stationary blade body 22 to be a predetermined position, the stationary blade body 22 is fixed by a jig.
The stator blade body 22 is joined to the stator blade ring segment 19 by performing TIG welding between the outer shroud portion 29 and the coupling member 23 as shown in FIG.
After joining, check for problems such as warping.

When the repair of the stator blade ring segment 19 is completed in this manner, the stator blade ring 13 is configured together with the other stator blade ring segment 19 and incorporated into the turbine 7. Thereby, the repair of the stationary blade ring 13 is completed.
In one repair, since one to several stator blade bodies 21 are exchanged, distortion or the like does not newly occur when viewed from the entire stator blade ring segment 19. For this reason, the reassembly of the stationary blade ring 13 is easily performed.
The removed stationary blade body 21 is melted and recycled. At this time, small debris can be recycled in the same manner by removing the weld bead and the like. Since the stationary blade body 21 is an expensive Ni / Co alloy, the economic effect is increased.

Thus, since the damaged stationary blade body 21 is replaced with a new stationary blade body 22, the reliability of the turbine 7 can be improved.
Moreover, since the stationary blade bodies 21 and 22 are joined to the coupling member by welding, the joint portion is not loosened by vibration during operation. Thereby, the reliability of the stationary blade ring 13 can be increased.
Furthermore, since only the damaged stationary blade body 21 is replaced, the working time is shortened and the cost can be reduced as compared with the replacement of the stationary blade ring 13 or the entire stationary blade ring segment 19.

In the present embodiment, the outer shroud portion 29 is joined to the coupling member 23 by welding, but is not limited to this.
For example, as shown in FIG. 14, a coupling member 24 having substantially the same structure as the coupling member 23 is installed on the opposite side of the inner shroud portion 31 with respect to the stationary blade 27, and the coupling member 24 and the inner shroud portion 31 are connected. You may make it join by partial welding.
In this way, the strength of the stationary blade ring segment 19 can be improved.
Further, since the coupling member 24 suppresses free movement of the inner shroud portion 31, it is not necessary to install a seal holder. For this reason, the structure of the stationary blade ring 13 can be simplified.

As shown in FIG. 15, the coupling member 24 has a trapezoidal cross-sectional shape, and the groove shape of the inner shroud portion 31 is formed so as to narrow toward the inside (opposite side to the stationary blade 27). It is desirable to do so.
In this case, even if the welded portion is broken and the coupling member 24 can freely move, the coupling member 24 does not move toward the rotating shaft 15, so safety is improved. .

  In the case where the inner shroud portion 31 is joined to the coupling member 24 by welding as shown in FIGS. 14 and 15, when the stationary blade body 21 is separated during repair, the outer shroud portion 29 is separated from the coupling member 23. It is necessary to separate the inner shroud portion 31 and separate it from the coupling member 24.

Further, as shown in FIG. 16, the stationary blade body 21 may be joined only by the coupling member 24 without attaching the coupling member 23.
In this case, since there is a possibility that the outer shroud portion 29 side tends to open in the circumferential direction, it is desirable to suppress this movement by appropriate means.
When repairing the stationary blade ring segment 19, the inner shroud portion 31 and the coupling member 24 are separated in the separation step.

  In addition, this invention is not limited to this embodiment, In the range which does not deviate from the summary of this invention, it can change suitably.

It is a schematic sectional drawing which shows the upper half part of the gas turbine using the stationary blade ring concerning one Embodiment of this invention. It is a side view which shows the stationary blade ring concerning one Embodiment of this invention. It is a perspective view which shows the stationary blade ring segment concerning one Embodiment of this invention. It is XX sectional drawing of FIG. It is the partial top view which looked at the stationary blade ring segment concerning one Embodiment of this invention from the outer side. It is a cross-sectional view which shows the mounting state of the coupling member concerning one Embodiment of this invention. It is a cross-sectional view which shows the state which cut off the outer shroud part and welding part concerning one Embodiment of this invention. It is a partial cross-sectional view which shows the state of the coupling member in FIG. It is sectional drawing which shows the state which incorporates the new stator blade body concerning one Embodiment of this invention. It is a cross-sectional view which shows the mounting state of the new stationary blade body concerning one Embodiment of this invention. It is a cross-sectional view which shows the mounting state of the coupling member concerning other embodiment of this invention. It is a cross-sectional view which shows the mounting state of the coupling member concerning other embodiment of this invention. It is a cross-sectional view which shows the mounting state of the coupling member concerning other embodiment of this invention. It is sectional drawing which shows the stationary blade body concerning other embodiment of this invention. It is a cross-sectional view which shows the mounting state of the coupling member concerning other embodiment of this invention. It is sectional drawing which shows the stationary blade body concerning other embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Gas turbine 3 Compressor 13 Stator blade ring 19 Stator blade ring segment 21 Stator blade body 23 Coupling member 24 Coupling member 27 Stator blade 29 Outer shroud part 31 Inner shroud part 37 Outer side surface 39 Groove 45 Welding part 53 Melting part P Circumferential direction

Claims (6)

A stationary blade divided body in which an inner shroud portion and an outer shroud portion divided so as to correspond to one stator blade are integrally formed at both ends of the stationary blade;
It is formed of an arc-shaped plate member and is installed on the opposite side to at least one of the inner shroud portion and the outer shroud portion of the plurality of stationary blade divided bodies adjacent in the circumferential direction. A coupling member,
A stator blade ring in which a part of a circumferential length of the stator blade divided body is welded to the coupling member to form a stator blade ring segment.   The stator blade ring according to claim 1, wherein a groove portion into which the joining member is inserted is provided in an inner shroud portion or the outer shroud portion where the joining member is installed.   The surface of the joining member opposite to the stationary blade is located on the stationary blade side relative to the surface of the inner shroud portion where the joining member is installed or the outer shroud portion opposite to the stationary blade. The stator blade ring according to claim 1 or 2.   The axial flow compressor provided with the stationary blade ring described in any one of Claims 1-3. A method for repairing a stator blade ring according to any one of claims 1 to 3,
A separation step of scraping the welded welded portion of the stationary blade segment in the stationary blade ring segment including the welded portion from the stationary blade segment side, and separating the stationary blade segment and the coupling member;
An exchange step of removing the separated stator blade divided body and fitting the newly formed stator blade divided body into the stator blade ring segment;
A method of repairing a stator blade ring, comprising: a joining step of joining the newly formed stator blade divided body and the coupling member by welding.   6. The method of repairing a stationary blade ring according to claim 5, wherein in the separation step, the surface of the coupling member is scraped off so that a melted portion accompanying welding becomes a predetermined ratio or less.

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