JP2003343280A - Method of repairing high temperature component by coupon and high temperature component having coupon - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of repairing a high temperature component by a coupon with which a damaged site of the high temperature component is repaired in a short period of time at a low cost, and also to provide a high temperature component having the coupon. <P>SOLUTION: A joint is formed on a peripheral part of a main body of the high temperature component which is made of a nickle base alloy or a cobalt base alloy, is used in an energy engine operated at a high temperature and is required to be of a high static and/or dynamic strength. A plate-like coupon member is made of a material substantially same as the material of the main body of the component, and a joint having a shape to be fitted to the joint on the peripheral part of the main body of the component is formed on a peripheral part of the coupon member. The joint of the coupon member is joined to the joint of the main body of the component to integrate the coupon member and the main body of the component. When the coupon member is damaged, the damaged coupon member is separated from the main body of the component at the joint, and a new coupon member is installed. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to high temperature parts of an energy engine such as a gas turbine, a steam turbine, a jet engine, etc., in particular, a vane portion and a shroud of a turbine engine, a combustor transition piece outlet portion, a moving blade portion and a platform. The present invention relates to a method for repairing a coupon of a high temperature component for repairing a portion of a split ring that is easily damaged, and a high temperature component having the coupon.

[0002]

2. Description of the Related Art Nickel-based superalloys and cobalt-based superalloys are used for turbine engine rotor blades and stationary blades (Japanese Patent Application Laid-Open No. 53-83608, Japanese Patent Application Laid-Open No. 2-2567).
No. 61), a combustor, a split ring (Japanese Patent Laid-Open No. 10-2).
No. 05305), and various high temperature parts such as nozzles. These high-temperature components are in direct contact with high-temperature gas (for example, a gas temperature of 1000 to 1200 ° C. at the exit of the combustor transition piece) and are subjected to severe heat cycles and corrosion, causing significant damage such as thermal fatigue cracks and erosion. For this reason, the parts deteriorate in a relatively short period of time, and the performance according to the originally designed specifications cannot be output, so that parts are frequently replaced or damaged parts are repaired. That is, if the damage received is fatal, the product is replaced with a new one, and if the damage is minor, the damaged part is brazed or welded for repair and used again.

[0003]

As described above, conventionally, parts are replaced or repaired according to the degree of damage. However, high-temperature parts have a large number of parts, and one high-temperature part is damaged by a plurality of parts. However, there are a large number of areas that require repairs. Since the nickel-base superalloy and the cobalt-base superalloy as the base materials are expensive materials, the repair cost will become excessive if the number of repair points increases, and in terms of cost, in extreme cases it will not be as much as when replacing parts. It will not change. In addition, when repairing a large number of parts, the repair period is extended by that much, and it is not possible to meet a short delivery time.

The present invention has been made to solve the above problems, and provides a method for repairing a high temperature component coupon and a high temperature component having a coupon for repairing a damaged portion of the high temperature component in a short period of time at low cost. The purpose is to provide.

[0005]

According to the present invention, there is provided a method for repairing a coupon of a high temperature component, wherein the static strength and / or dynamics of a high temperature component body made of a nickel base alloy or a cobalt base alloy used in an energy engine operated at a high temperature. A joint is formed at the peripheral portion where the mechanical strength is required, and a plate-shaped coupon member of substantially the same material as the high temperature component body is prepared, and the side of the high temperature component body is provided at the peripheral portion of the coupon member. Forming a joint having a shape that matches the edge joint, joining the joint of the coupon member to the joint of the high temperature component body, and integrating the coupon member and the high temperature component body; If the damaged coupon member is damaged, the damaged coupon member is separated from the high temperature component body at the joint and a new coupon member is attached.

A high temperature component having a coupon according to the present invention is a side where high static component strength and / or dynamic strength of a high temperature component body made of a nickel base alloy or a cobalt base alloy used in an energy engine operated at high temperature is required. A plate-shaped coupon member, which is substantially the same material as the high-temperature component body, is joined to the edge portion through a joint.

The high temperature component coupon repairing method of the present invention can be suitably applied to any of the vane portion and shroud of the turbine engine, the combustor tail pipe outlet portion, the blade portion and platform, the split ring, etc. As a high temperature component having a vane portion and a shroud of a turbine engine,
A combustor transition piece outlet section, a rotor blade section and platform, and a split ring are each provided.

The vane shroud, the combustor tail pipe outlet, the rotor blade platform, and the edges and corner edges of the split ring are extremely susceptible to damage such as erosion and high temperature oxidation, which may shorten the life of the entire member. is there. Therefore, in the present invention, the edge portions of these members are used as a coupon having a joint structure that is easily attached to and detached from the main body, and the joint between the main body and the coupon has a fitting structure or a butt welding structure to ensure a certain level of strength or more. To adopt.

In the case of a fitting structure, it is preferable to use a dovetail groove fitting in which a convex portion is fitted in a concave groove portion. In the initial coupon repair (or at the time of manufacture), it is preferable to form the concave groove portion on the coupon side and the convex portion on the main body side. This is because in the second and subsequent coupon repairs, a margin for forming the concave groove portion on the main body side can be reserved when the peripheral edge portion is significantly damaged so that the convex portion cannot be formed on the main body side.

In the case of a joint having a butt welded structure,
In order to guarantee a certain level of strength, double-sided butt welding or brazing with a groove on both the front and back sides is used. Arc welding or brazing is used for butt welding. It is preferable to use TIG welding for arc welding. TIG
It is preferable to use IN625 alloy (Ni-based composition) or the like as the filler metal for welding.

The nickel-base alloy brazing material used for brazing repair is, for example, a low melting point alloy powder containing Ni, Cr, Co, W, Ti, Al, B and having a melting point of 1080 to 1270 ° C. and Ni, Cr, Co, W. It is preferable that the high melting point alloy powder having a melting point of 1200 ° C. or higher containing ## STR3 ## is mixed at a ratio of 3: 7 to 7: 3. The nickel-based alloy as the base material is, for example, Inconel 738LC (Cr 15.70 to 16.30).
%, Co8.00 to 9.00%, Ti3.20 to 3.70%, Al3.20 to
3.70%, W2.40-2.80%, Mo1.50-2.00%, Ta1.50
.About.2.00%, C0.09 to 0.13%, B0.01% or less, P0.01% or less, S0.01% or less), and as an example of the composition of the low melting point Ni-based alloy powder, Ni-8- 12Cr-16 ~ 2
0Co-2 to 3.5Mo-1.5 to 2.5W-5 to 9Ta-7.5 to 10T
i-8.5 to 10.5 Al-1 to 3Nb-0.5 to 3.5B-0.35Zr
As an example of the composition of the high melting point Ni-based alloy powder, Ni-
16-18Cr--5Co--3.5W--1.0Ta--1.0Ti
-~ 1.0Al-0.15-0.3C-0.01-0.03B- ~ 0.1Zr
Can be given respectively. If the mixing ratio of the low melting point Ni alloy powder is less than 30% by weight, sintering will not proceed sufficiently. On the other hand, if the blending ratio of the low melting point Ni alloy powder exceeds 70% by weight, the liquid phase becomes too large and sufficient strength cannot be obtained.

The heating is preferably carried out at a temperature of 1080 to 1270 ° C. and a condition of holding for 2 to 24 hours. Here, if the heating temperature is lower than 1080 ° C., the liquid phase due to the capillary phenomenon does not occur, and if the heating temperature exceeds 1270 ° C., the base material is more easily melted. Further, in the present invention, it is preferable to further perform stepwise heat treatment after the above heat treatment (sintering). Specifically, it is heated at 1120 ° C. ± 10 ° C. for 2 to 4 hours (the former), and further at 850 ° C. ± 10 ° C. for 16 to 24.
Heat for an hour (latter).

Here, the former heating is performed by the γ'phase (N) in the base metal precipitated in the cooling process in the heat treatment for sintering.
i ₃ Al intermetallic compound), the temperature is set to 1120 ° C. to prevent solid solution of the γ ′ phase and initial melting, and the treatment time is diffusion of each alloy component. In order to proceed sufficiently, The latter heating is performed in order to uniformly precipitate the γ ′ phase, and is 850 ° C. in order to make the precipitation state of the γ ′ phase uniform and fine, and 16 to 24 in order to precipitate in accordance with the alloy composition. Time processing.

[0014]

Various preferred embodiments of the present invention will be described below with reference to the accompanying drawings. In the present embodiment, an example will be described in which various types of high temperature parts used in a gas turbine engine for power generation are repaired by brazing.

As shown in FIG. 1, a gas turbine engine 1 for power generation includes a fuel supply pipe 2, 4, nozzles 3, 5, a combustor inner cylinder 6, a combustor tail cylinder 7, a stationary blade 8 and a moving blade 9. The turbine blade 10, the split ring 11, the compressor (supercharger) 12, the compressed air introduction port 13, and the bypass valve 14 are provided, and the main fuel flows from the plurality of premixing nozzles 3 through the fuel supply pipe 2 into the combustor. The air that is injected into the compressor (supercharger) 12 through the compressed air introduction port 13 is mixed and burned, and the combustion gas rotates the turbine blade 10. There is. At the start of operation, pilot fuel is supplied to the fuel supply pipe 4 and injected from the pilot nozzle 5 for ignition.

The combustor comprises an inner cylinder 6 in which the injection holes of the nozzles 3 and 5 are open, and a tail cylinder 7 following the inner cylinder. The rear end of the combustor transition piece 7 is opened so as to blow the combustion gas to the turbine blade 10. Also, the combustor transition piece 7
A bypass pipe provided with a bypass valve 14 is connected in the middle of. The peripheral wall forming the combustor transition piece 7 is, for example, IN73.
It consists of a nickel-base heat-resistant alloy such as 8LC.

A stationary blade 8 and a moving blade 9 which form a turbine blade 10.
And are arranged alternately in the axial direction. The shrouds 82 and 83 for fixing the stationary blade 8 are made of a cobalt-based heat-resistant alloy such as ECY768. The platform 92 of the rotor blade 9 is made of a nickel-base heat-resistant alloy such as Tomilloy. In FIG. 6, reference numeral 94 indicates a through hole for air cooling, reference numeral 93 indicates a fixed portion, and reference numeral 99 indicates a damaged portion.

The split ring 11 is provided on the outer peripheral side in order to prevent the combustion gas from leaking outside through the gap between the stationary blade 8 and the moving blade 9. The peripheral wall forming the split ring 11 is made of a cobalt-base heat-resistant alloy such as Hastelloy X.

Example 1 Next, referring to FIGS. 2 and 3, as Example 1, a Co-based alloy (for example, ECY76) was used.
The case of coupon repair of the vane shroud of the gas turbine engine consisting of 8) will be described.

The stationary vane 8 is supported by a pair of rectangular shrouds 20 as shown in FIG. The outer shroud 82 is a member for holding the vane body 81 of the vane in a casing (not shown). The inner shroud 83 is a member for holding a seal structure (not shown). Coupons 20 are attached to both side edges of each shroud 82, 83.

The coupon 20 is fitted to the edge portions of the shrouds 82 and 83 as shown in FIG. This fitting joint is a dovetail groove joint in which the convex portion 24 on the shroud 82, 83 side is fitted in the groove 22 on the coupon 20 side. The coupon 20 has a length corresponding to the length of one side of the shrouds 82, 83 (about 200 mm) and a thickness t of 10 to 1.
The width W is about 5 mm and the width W is about 20 to 30 mm. When the coupon 20 is fitted to the peripheral portions of the shrouds 82, 83, the coupon 20 and the shrouds 82, 83 are shown as shown.
And is the same on both sides. Although the coupon 20 is made of the same material as the shrouds 82 and 83 in this embodiment, if the shrouds 82 and 83 are resistant to structural deterioration and have heat resistance and erosion resistance, the shroud 82 and 83 Other alloys different from 83 may be used. In addition, stoppers (not shown) are provided at both ends of the coupon 20 in the longitudinal direction to prevent the coupon 20 from slipping out. It is desirable to use welding or brazing for the stopper.

According to the first embodiment, when erosion occurs as shown in FIG. 2, the erosion damaged portion 8 is formed.
Since only the coupon 20 of 9 is removed from the peripheral portions of the shrouds 82 and 83 and a new coupon is attached to the shroud 82, 83, the repair process can be simplified and shortened as compared with the conventional one, and the repair can be completed quickly. it can. For this reason,
It will be possible to handle short delivery times.

In the first embodiment, the coupon joint has a mating structure, but a butt welded joint structure as shown in FIG. 4 may be used.

Example 2 Next, referring to FIGS. 5 and 4, as Example 2, a Ni-based alloy [for example, Tomyloy (To
A case of repairing the coupon of the combustor tail tube outlet made of milloy)] will be described.

The combustor transition piece outlet portion 71 has an air cooling fin structure as shown in FIG. 5, and includes an outer fin plate 72, an inner fin plate 73, a cooling passage 74, a cooling air inlet 75, a cooling air outlet 76, It has a coupon 20. As shown in FIG. 4, the coupon 20 is butt-welded to the edge portions of the inner and outer fin plates 72 and 73. The coupon 20 has a length corresponding to one side of the fin plates 72, 73 and a thickness t of 5
It is about 10 mm and the width W is about 300 mm. Coupon 2
When 0 is welded to the edges of the inner and outer fin plates 72 and 73, the fin plates 72 and 73 are flush with each other as shown in the figure.

A method of repairing a coupon when the edge portions of the fin plates 72 and 73 at the combustor tail tube outlet are damaged by erosion will be described.

Fin plate 7 including erosion damage site
The edges of 2, 73 are cut off to a predetermined width, the cut surface is ground with a grindstone or the like to form a groove with an appropriate inclination, and this groove surface is degreased and washed. Coupon 2 in the groove of the fin plates 72, 73
The groove of No. 0 is aligned, the filler metal of the Tomilloy alloy is added, and TIG welding is performed. Furthermore, after the surplus welded portion is ground with a grindstone or the like to make the surface of the repaired portion flat, 1120 ° C. × 2 hours + 8 to increase the strength.
Two-step heat treatment (solution treatment and aging) at 50 ° C x 24 hours
I went.

According to the second embodiment, it was possible to obtain a coupon repairing portion whose strength was sufficiently guaranteed.

(Embodiment 3) Next, with reference to FIGS. 6 and 3, a case of repairing a coupon of a gas turbine blade platform made of a Ni-based alloy (for example, IN738LC, IN738LC, USA) will be described as Embodiment 3. To do.

Since the moving blade 9 is used under high temperature and severe conditions, thermal fatigue cracks and erosion corrosion are likely to occur at the edge of the platform 92. In order to safely operate the gas turbine, it is necessary to repair these cracks and thinned parts.

As shown in FIG. 6, the turbine rotor blade 9 includes a blade main body 91 extending in the circumferential direction, a platform 92 provided at a base portion on the inner peripheral side of the blade main body 91, and an inner peripheral side of the platform 92. It is a precision casting product that is integrated with the fixing portion 93 provided in the. The wing body 91 has a hollow structure,
In order to air-cool the blade body 91, a large number of holes 94 penetrating the blade body from the front surface side to the back surface side are formed in series along the length of the blade body 91. Coupons 20 are attached to both edges of the platform 92, respectively.

The coupon 20 is fitted to the edge of the platform 92. This fitting joint is a dovetail groove fitting in which the convex portion of the platform 92 is fitted into the groove 22 on the coupon 20 side. The coupon 20 has a length of one side of the platform 92 (about 200 mm).
The thickness t is about 12 to 18 mm and the width W is about 20 to
It is about 30 mm. When the coupon 20 is fitted to the peripheral portion of the platform 92, the coupon 20 and the platform 92 are flush with each other as shown in the figure.

According to the third embodiment, when thermal fatigue cracking or erosion occurs as shown in FIG. 6, only the coupon 20 of the erosion damaged portion 99 is removed from the edge portion of the platform 92, and the Since it is only necessary to attach a new coupon, the repair process is simpler and shorter than in the past, and the repair can be completed quickly. Therefore, it is possible to meet a short delivery time.

Example 4 Next, with reference to FIGS. 7 and 3, a case will be described as Example 4 in which a split ring made of a Ni-based alloy (for example, Hastelloy X manufactured by Hynes Stellite Co.) is repaired. .

The split ring 11 prevents the combustion gas from leaking outside through the gap between the stationary blade 8 and the moving blade 9, and surrounds the outer periphery of the moving blade 9 over the entire circumference as shown in FIG. Are arranged as follows. The split ring 11 is fixedly supported by a pair of members 15 on a turbine frame (not shown). A plurality of cooling holes 11a for air cooling are formed in the split ring 11. Coupons 2 are provided at both ends of the split ring 11 in the width direction.
0 is attached respectively. The coupon 20 has a fitting joint structure shown in FIG.

According to the fourth embodiment, when erosion occurs, it is sufficient to remove only the coupon 20 of the damaged erosion part from the end of the split ring 11 and attach a new coupon to it. Compared with, the repair process is simple and shortened, and the repair can be completed quickly. Therefore, it is possible to meet a short delivery time.

[0037]

As described in detail above, according to the present invention, a damaged portion of a high temperature component can be repaired in a short time at low cost. For this reason, it is possible to repair the damaged parts that were conventionally replaced with new ones and discarded, and to reuse them, so that the maintenance cost can be significantly reduced. Further, since the repair process is shortened, it becomes possible to cope with a short delivery time.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a main part showing an outline of a gas turbine.

FIG. 2 is a perspective view showing the appearance of a turbine vane.

FIG. 3 is a perspective view showing a part of a coupon member having a fitting structure.

FIG. 4 is a perspective view showing a part of a coupon member having a welded structure.

FIG. 5 is a perspective view showing an external appearance of a combustor transition piece outlet.

FIG. 6 is a perspective view showing an appearance of a turbine rotor blade.

FIG. 7 is a side sectional view showing a split ring.

[Explanation of symbols]

2, 4 ... Fuel supply pipe, 3, 5 ... Nozzle, 6 ... Combustor inner cylinder, 7 ... Combustor tail cylinder, 71 ... Tail cylinder outlet, 72, 73 ...
Fin plate, 74 ... Cooling passage, 75 ... Cooling air inlet, 76
... Cooling air outlet, 8 ... Static vane, 81 ... Blade body, 82 ... Outer shroud, 83 ... Inner shroud, 89 ... Damaged portion, 9
... moving blade, 91 ... wing body, 92 ... platform, 93
... Fixed part, 94 ... Cooling hole, 99 ... Damaged part, 10 ... Turbine blade, 11 ... Split ring, 12 ... Compressor (supercharger), 13 ...
Compressed air inlet port, 14 ... Bypass valve, 20, 20A ... Coupon (coupon member), 22 ... Dovetail groove, 24 ... Fitting convex part, 26 ... Butt welding part.

Claims (6)

[Claims] 1. A joint is formed at a peripheral portion where static strength and / or dynamic strength of a high temperature component made of a nickel base alloy or a cobalt base alloy used for an energy engine operated at high temperature is required, and Preparing a plate-shaped coupon member of substantially the same material as the high temperature component body, and forming a joint having a shape matching the edge joint of the high temperature component body at the edge portion of the coupon member; Joining the joint of the member to the joint of the high temperature component body, integrating the coupon member and the high temperature component body, and if the coupon member is damaged, the damaged coupon member at the joint And a step of attaching a new coupon member separately from the high temperature component body, the method of repairing a high temperature component coupon. 2. The method according to claim 1, wherein the edge joint has a fitting structure. 3. The method of claim 1, wherein the edge joint is a butt welded structure. 4. The method according to claim 1, wherein the edge joint is linear, and the front and back surfaces of the coupon member and the front and back surfaces of the high temperature component body are substantially flush with each other. 5. A high temperature component main body used in an energy engine operated at high temperature, comprising a high temperature component main body made of a nickel-based alloy or a cobalt-based alloy at a peripheral portion where static strength and / or dynamic strength is required. A high-temperature component having a coupon, characterized in that plate-shaped coupon members made of substantially the same material are joined via a joint. 6. The high temperature component body is any one of a vane portion and a shroud of a turbine engine, a combustor transition piece outlet portion, a blade portion and platform of a turbine, and a split ring. The high temperature component described in 5.