JP2013194694A - Method for repairing gas turbine moving blade and gas turbine moving blade - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for repairing a gas turbine moving blade by which the gas turbine moving blade can be repaired without reducing thickness of a base material part, and to provide a gas turbine moving blade.SOLUTION: A method for repairing a gas turbine moving blade includes steps of: removing a worn portion of a blade tip 10a and working the blade tip 10a into a plane 13; and performing build-up welding on the plane 13 to form a built-up portion 14 with a predetermined height and thickness. The method further includes steps of: working a distal end of the built-up portion 14 into the shape same as the original shape of the blade tip 10a and forming a step 23 in such a way that an outer side face 20 of the built-up portion 14 is located inside of the gas turbine moving blade 10 rather than an outer side face 21 of a base material part 11 constituting the blade tip 10a; applying build-up processing to the outer side face 21 of the built-up portion 14 and eliminating a step between the outer side face 21 of the built-up portion 14 and the outer side face 21 of the base material part 11, thereby providing the same shape as the original shape of the blade tip 10a; and performing solution heat treatment and aging heat treatment.

Description

  Embodiments described herein relate generally to a gas turbine blade repair method and a gas turbine blade repaired by the repair method.

  In the gas turbine, the thermal efficiency can be improved by increasing the combustion gas temperature. For this reason, in conventional gas turbines, the mainstream is that the inlet gas temperature of the first stage stationary blade is 1100 ° C., but recently, those whose temperatures are 1300 ° C. and 1500 ° C. have been developed. .

  The blade tip of the gas turbine blade is exposed to a high-temperature combustion gas of 1000 ° C. or higher. Therefore, at the blade tip of the gas turbine blade, wear (thinning) proceeds due to oxidation by high-temperature combustion gas and erosion from the combustion gas passing through the gas turbine blade. Further, the blade tip portion of the gas turbine rotor blade is worn (thinned) by sliding with the shroud segment disposed oppositely.

  When such wear occurs in the gas turbine blade, it is generally repaired by overlay welding. In this repair, the blade tip is formed into a shape that is easy to build-up, and build-up welding is performed, finishing is performed by machining or a grindstone, and the blade is formed into the original blade shape before wear.

JP 2012-620 A

  In the above-described conventional method for repairing the blade tip of the gas turbine rotor blade, in the finishing process after build-up welding, in order to smooth the flow of the working fluid on the blade surface, It is necessary to finish the boundary smoothly so that there are no irregularities. Therefore, in the finishing process, the surface of the base material part is also slightly shaved.

  When such repairs are performed a plurality of times, the thickness of the base material portion becomes thin, and the tip of the blade is likely to break during operation, or it may be discarded due to being less than the allowable thickness during repair. is there. In addition, the difference between the shape of the turbine rotor blade that has been repaired a plurality of times and the shape of the designed blade may increase, and the performance may deteriorate.

  A problem to be solved by the present invention is a gas turbine rotor blade repair method capable of repairing a gas turbine rotor blade without reducing the thickness of the base material portion, and a gas turbine rotor blade repaired by the repair method. Is to provide.

  In the gas turbine rotor blade repair method of the embodiment, the tip of the gas turbine rotor blade is repaired. In the gas turbine rotor blade repairing method, a worn portion removing process of removing the worn portion of the blade tip and processing the blade tip into a flat surface, and overlay welding to the blade tip processed into a flat surface, And a build-up welding process for forming a build-up part having a predetermined thickness and a predetermined thickness.

  Further, in the gas turbine rotor blade repairing method, the front end portion and the inner side portion of the build-up portion are processed into the same shape as the shape of the initial tip of the blade before wear, and the outer surface of the build-up portion However, the step forming step of forming the step by processing the build-up portion so as to be on the inner side of the gas turbine rotor blade than the outer side surface of the base portion constituting the blade tip, and the build-up portion Step build-up is applied to the outer surface to eliminate the step between the outer surface of the built-up portion and the outer surface of the base material portion, and to have the same shape as the initial shape of the blade tip before wear. And a heat treatment step for performing solution heat treatment and aging heat treatment.

It is a perspective view which shows the gas turbine rotor blade with which the blade | tip tip was worn out repaired with the repair method of the gas turbine rotor blade of 1st Embodiment. It is an AA cross section of FIG. 1, and is a figure which shows the cross section of the blade tip of a gas turbine rotor blade. It is a figure which shows the process of the repair method of the gas turbine rotor blade of 1st Embodiment. It is a figure which shows the cross section corresponded to the AA cross section of FIG. 1 for demonstrating the process of the repair method of the gas turbine rotor blade of 1st Embodiment. It is a figure which shows the cross section corresponded to the AA cross section of FIG. 1 for demonstrating the process of the repair method of the gas turbine rotor blade of 1st Embodiment. It is a figure for demonstrating the laser welding method. It is a figure which shows the cross section corresponded to the AA cross section of FIG. 1 for demonstrating the process of the repair method of the gas turbine rotor blade of 1st Embodiment. It is a figure which shows the cross section corresponded to the AA cross section of FIG. 1 for demonstrating the process of the repair method of the gas turbine rotor blade of 1st Embodiment. It is a figure which shows the cross section corresponded to the AA cross section of FIG. 1 for demonstrating the process of the repair method of the gas turbine rotor blade of 1st Embodiment. It is a figure which shows the process of the repair method of the gas turbine rotor blade of 2nd Embodiment. It is a figure which shows the cross section corresponded to the AA cross section of FIG. 1 for demonstrating the process of the repair method of the gas turbine rotor blade of 2nd Embodiment. It is a figure which shows the cross section corresponded to the AA cross section of FIG. 1 for demonstrating the process of the repair method of the gas turbine rotor blade of 2nd Embodiment. It is a figure which shows the cross section corresponded to the AA cross section of FIG. 1 for demonstrating the process of the repair method of the gas turbine rotor blade of 2nd Embodiment. It is a figure which shows the cross section corresponded to the AA cross section of FIG. 1 for demonstrating the process of the repair method of the gas turbine rotor blade of 2nd Embodiment. It is a figure which shows the cross section corresponded to the AA cross section of FIG. 1 for demonstrating the process of the repair method of the gas turbine rotor blade of 2nd Embodiment. It is a figure which shows the process of the repair method of the gas turbine rotor blade of 3rd Embodiment. It is a figure which shows the cross section equivalent to the AA cross section of FIG. 1 after the wear part removal process of the repair method of the gas turbine rotor blade of 3rd Embodiment. It is a figure which shows the cross section equivalent to the AA cross section of FIG. 1 for demonstrating the blade tip formation process of the repair method of the gas turbine rotor blade of 3rd Embodiment. It is a figure which shows the cross section equivalent to the AA cross section of FIG. 1 for demonstrating the blade tip formation process of the repair method of the gas turbine rotor blade of 3rd Embodiment. It is a figure which shows the cross section equivalent to the AA cross section of FIG. 1 for demonstrating the blade tip formation process of the repair method of the gas turbine rotor blade of 3rd Embodiment.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a perspective view showing a gas turbine rotor blade 10 with a blade tip 10a worn out, which is repaired by the gas turbine rotor blade repair method of the first embodiment. FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1 and showing a cross section of the blade tip 10a of the gas turbine rotor blade 10. FIG. FIG. 3 is a diagram illustrating a process of the gas turbine rotor blade repair method according to the first embodiment. FIGS. 4 to 5 and FIGS. 7 to 9 are cross-sectional views corresponding to the A-A cross section of FIG. 1 for explaining the steps of the gas turbine rotor blade repair method according to the first embodiment. is there. FIG. 6 is a diagram for explaining the laser welding method. In addition, in FIGS. 1-2 and FIGS. 4-5, the worn part is shown with the broken line.

  In the description of the gas turbine rotor blade repair method according to the first embodiment, the gas turbine rotor blade 10 will be described with an example in which the blade tip 10a is configured by a squealer portion. The gas turbine rotor blade repair method of the first embodiment can also be applied to gas turbine rotor blades.

  As shown in FIG. 1 and FIG. 2, the blade tip 10a of the gas turbine rotor blade 10 is worn by being oxidized by the combustion gas or being eroded by the combustion gas passing through the gas turbine rotor blade 10, and has an uneven surface shape. Become. Further, the blade tip 10a of the gas turbine rotor blade 10 is worn out by sliding with the shroud segments arranged opposite to each other. Here, examples of wear include thinning.

  As described above, when the blade tip 10a of the gas turbine rotor blade 10 is worn, the repair process is performed by performing the process of each step shown in FIG. A specific repair method will be described.

  First, the gas turbine rotor blade 10 to be repaired is subjected to visual observation, fluorescent penetrant inspection (FPT), and the like, and the part of wear and the like is examined. Subsequently, in order to improve weldability, the gas turbine rotor blade 10 to be repaired is maintained at a temperature of, for example, about 1120 to 1320 ° C. for a predetermined time, and solution heat treatment is performed. After performing these receiving processes, the following repair process is performed.

  When the coating layer 15 is formed on the blade surface of the gas turbine rotor blade 10 in which the blade tip 10a is worn as shown in FIG. 2, the coating layer 15 is removed and the base material portion 11 is exposed. (Coating layer removal step S100).

  The coating layer 15 is, for example, a corrosion-resistant coating layer made of a metal material formed on the surface of the base material part 11 or the built-up part 14, and a heat shield made of a ceramic material formed by being laminated on the surface of the corrosion-resistant coating layer. Consists of a coating layer. These coating layers 15 are removed by, for example, blasting or chemical treatment using a chemical such as a hot acidic solution. If the coating layer 15 is not formed on the blade surface of the gas turbine rotor blade 10, the coating layer removal step S100 is not necessary.

  Subsequently, as shown in FIG. 4, the worn part 12 of the blade tip 10 a is removed by, for example, a grinder such as a grinder, and the blade tip 10 a is processed into the flat surface 13 (worn part removing step S <b> 101).

  Here, an example is shown in which the plane 13 of the blade tip 10a is processed so as to be a plane parallel to the end surface of the original blade tip before thinning, as shown in FIG.

  Then, the build-up part 14 of predetermined | prescribed height and predetermined | prescribed thickness is formed in the blade | wing tip 10a processed into the plane 13 (build-up welding process S102).

  In this build-up welding, for example, as shown in FIG. 6, the laser irradiated from the laser torch 110 in the camber line direction (left and right direction in FIG. 6) of the gas turbine rotor blade 10 along the plane 13 of the blade tip 10 a. While scanning the light 111, the powder 112 of the cladding material is supplied from the powder supply device 113 to the front of the laser beam 111. The supplied overlaying material powder 112 is melted by the heat of the laser beam 111 and welded to the flat surface 13 of the blade tip 10a. This laser welding is repeatedly performed, and the weld beads 114 are stacked in multiple layers and built up to form the built-up portion 14 shown in FIG.

  While the laser torch 110 is scanned in a direction perpendicular to the camber line of the gas turbine rotor blade 10 (in FIG. 6, the direction perpendicular to the paper surface), the weld beads are built up in multiple layers to form the built-up portion 14. May be.

As a laser used for laser welding, for example, a CO ₂ laser or a YAG laser can be used. The supply amount of the powder 112 of the build-up material to be supplied depends on the output of the laser, that is, the energy of the laser beam 111, and the larger the laser output, the more powder 112 can be supplied and welding can be performed.

  Here, in order to prevent solidification cracking during welding, it is important to reduce the laser output as much as possible to suppress heat input during welding. For this reason, it is preferable to repeatedly build-up welding while irradiating the laser beam 111 having a minimum energy that can melt the powder 112 of the build-up material, and stack and weld the weld beads 114. In this way, by adjusting the output of the laser and irradiating the laser beam 111 having a minimum energy enough to melt the overlaying material powder 112, the weld interface at the welding interface due to accumulation of thermal strain during welding is used. Generation of cracks can be suppressed.

  The gas turbine rotor blade 10 is made of, for example, a Ni-based heat-resistant alloy such as IN738 (trade name) or GTD111 (trade name). The build-up material constituting the build-up portion 14 is the same material as the Ni-base heat-resistant alloy forming these gas turbine rotor blades 10 or a material having similar oxidation resistance and excellent weldability. Is preferred. Specifically, IN625 (trade name), IN600 (trade name), or the like can be used as the overlay material.

  In addition, the formation method of the build-up part 14 is not restricted to an above-described method, You may use the well-known method currently used in repair of the gas turbine rotor blade 10. FIG.

  As shown in FIG. 5, the build-up portion 14 is higher in the height direction and thickness of the gas turbine rotor blade 10 than the initial blade tip shape before wear (the portion indicated by the broken line in FIG. 5). It is formed so as to protrude in the circumferential direction which is the direction (the outer side and the inner side of the gas turbine rotor blade 10).

  Then, as shown in FIG. 7, the front-end | tip part and inner side part of the build-up part 14 are processed into the same shape as the shape of the original blade | wing tip 10a before wearing out. Thereby, the outer peripheral end surface 24 and the inner side surface 25 of the built-up portion 14 are formed.

  Further, the build-up portion 14 is processed so that the outer surface 20 of the build-up portion 14 is on the inner side of the gas turbine rotor blade than the outer surface 21 of the base member portion 11 constituting the blade tip 10a. Is formed (step forming step S103). That is, as shown in FIG. 7, the outer side surface 20 of the build-up portion 14 is configured to be recessed more to the inner side of the gas turbine rotor blade than the outer side surface 21 of the base material portion 11. The build-up portion 14 is processed using, for example, a grinder such as a grinder.

  Subsequently, as shown in FIG. 8, the outside surface 20 of the built-up portion 14 is subjected to a build-up process to form the built-up portion 30, and the outside surface 20 of the built-up portion 14 and the outside surface 21 of the base material portion 11. And the same shape as the original shape of the blade tip 10a before being worn out (step buildup step S104).

  As a result, the outer surface 31 of the built-up portion 30 that is built up on the outer surface 20 of the built-up portion 14 becomes a surface that is smoothly connected to the outer surface 21 of the base material portion 11.

  In the step buildup step S104, the buildup portion 30 is formed by, for example, thermal spraying, cold spraying, diffusion brazing, or the like. Here, when overlaying in diffusion brazing, for example, a molding die is used so that the brazing material does not flow out of the step 23. At this time, it is preferable to use a mold made of a ceramic plate such as high-purity alumina, zirconia, or mullite that has poor bondability to the brazing material in order to easily remove the mold from the built-up portion 30. Since the centrifugal stress applied to the blade tip is small, the material that fills the step 23 does not require strength.

  As the build-up material constituting the build-up part 30, for example, the same material as the build-up material constituting the build-up part 14, or MCrAlY which is an oxidation-resistant coating material (CoNiCrAlY or NiCoCrAlY where M is made of Co and Ni, etc.) ) Can be used.

  Next, as shown in FIG. 9, the gas turbine rotor blade 10 is subjected to a known coating process to form a coating layer 15 on the blade surface of the gas turbine rotor blade 10 (coating process step S105). In the case where the coating layer 15 is not formed on the blade surface of the gas turbine rotor blade 10, the coating process step S105 is not necessary.

  As described above, the coating layer 15 is, for example, a corrosion-resistant coating layer made of a metal material formed on the surface of the base material portion 11 or the built-up portion 14, and ceramics formed by laminating on the surface of the corrosion-resistant coating layer. It consists of a thermal barrier coating layer made of material. The gas turbine rotor blade 10 having the coating layer 15 including the corrosion-resistant coating layer and the thermal barrier coating layer is widely used in general.

  The corrosion-resistant coating layer is formed by, for example, high-speed flame spraying (HVOF), vacuum plasma spraying (VPS), electron beam physical vapor deposition (EB-PVD), etc., and the thermal barrier coating layer is, for example, atmospheric plasma spraying (APS) Formed by.

  Although FIG. 8 shows an example in which the coating layer 15 is not formed on the outer peripheral end surface 24 of the built-up portion 14, the coating layer 15 may be formed on the outer peripheral end surface 24.

  Subsequently, solution heat treatment and aging heat treatment are performed (heat treatment step S106). The solution heat treatment is performed in order to release welding distortion and to form a solid solution of the γ ′ phase precipitated during welding in the γ phase, and the gas turbine blade 10 is maintained at a temperature of about 1120 to 1320 ° C. for a predetermined time. The aging heat treatment is performed to precipitate the γ ′ phase and strengthen the material. The gas turbine blade 10 is heated to about 700 to 900 ° C. and held for a predetermined time.

  The heat-treated gas turbine rotor blade 10 is subjected to visual observation, fluorescence penetration inspection (FPT), and the like, and final inspections such as the presence or absence of wear are performed.

  Through the above repair process, the gas turbine rotor blade 10 in which the wear of the blade tip 10a is repaired is obtained.

  As described above, according to the gas turbine rotor blade repairing method of the first embodiment, the step 23 is formed on the outer surface 20 of the built-up portion 14, and the step 23 is built up to form the base material. A surface smoothly connected to the outer surface 21 of the portion 11 can be formed. That is, the boundary between the base material portion 11 and the built-up portion 30 is finished smoothly without unevenness. In this way, the gas turbine rotor blade 10 can be repaired without reducing the thickness of the base material portion 11.

(Second Embodiment)
FIG. 10 is a diagram illustrating a process of the gas turbine rotor blade repair method according to the second embodiment. As in the case of the gas turbine rotor blade repair method of the first embodiment, in the case of repair of the gas turbine rotor blade 10 that does not have the coating layer 15 on the blade surface, the coating layer removal step S110 and the coating are performed. Processing step S116 is not necessary.

  FIGS. 11-15 is a figure which shows the cross section equivalent to the AA cross section of FIG. 1 for demonstrating the process of the repair method of the gas turbine rotor blade of 2nd Embodiment.

  Here, the receiving process, the coating layer removing process S110 and the worn part removing process S111, and the build-up welding process S112 are the receiving process, the coating layer removing process S100, the worn part removing process S101 and the first embodiment. This is the same process as the build-up welding process S102. FIG. 11 shows the configuration after the overlay welding step S112.

  After the build-up welding step S112, as shown in FIG. 12, the tip portion and the inner portion of the build-up portion 14 are processed into the same shape as that of the initial blade tip 10a before being worn out. Thereby, the outer peripheral end surface 24 and the inner side surface 25 of the built-up portion 14 are formed.

  Further, the build-up portion 14 is processed so that the outer surface 20 of the build-up portion 14 is on the outer side of the gas turbine rotor blade with respect to the outer surface 21 of the base material portion 11 constituting the blade tip 10a. Is formed (step forming step S113). That is, as shown in FIG. 12, the outer surface 20 of the built-up portion 14 is configured to protrude to the outside of the gas turbine rotor blade from the outer surface 21 of the base material portion 11.

  In addition, the thickness of the build-up part 14 is formed to such a thickness that at least the step 40 can be formed. The build-up portion 14 is processed using, for example, a grinder such as a grinder.

  Subsequently, as shown in FIG. 13, the outside surface 21 of the base material portion 11 is subjected to a build-up process to form a base material build-up portion 41, and the outside surface 21 of the base material portion 11 and the outside of the build-up portion 14 are outside. The step 40 with the side surface 20 is eliminated (step build-up process S114).

  Note that the build-up process is the same process as the build-up process in the step build-up process S104 of the first embodiment. For example, MCrAlY which is an oxidation-resistant coating material can be used as the build-up material constituting the base material build-up portion 41.

  Subsequently, as shown in FIG. 14, the base material built-up portion 41 and the built-up portion 14 formed on the outer surface 21 of the base material portion 11 are processed and have the same shape as the initial blade tip 10 a before being worn out. (Outside surface forming step S115).

  At this time, a part of the build-up portion 14 and the base build-up portion 41 are scraped off by, for example, a grinder such as a grinder. Thereby, the outer side surface 21 of the base material part 11 turns into a surface smoothly connected with the outer side surface 20 of the build-up part 14. FIG. Moreover, in this process, although the base material build-up part 41 is scraped off, the base material part 11 itself is not shaved.

  The subsequent coating processing step S116 and heat treatment step S117 are the same processing as the coating processing step S105 and heat treatment step S106 of the first embodiment. The heat-treated gas turbine rotor blade 10 is subjected to a final inspection in the same manner as in the first embodiment.

  Through the above-described repairing process, as shown in FIG. 15, the gas turbine rotor blade 10 in which the wear of the blade tip 10a is repaired is obtained.

  As described above, according to the gas turbine rotor blade repairing method of the second embodiment, the step 40 is formed on the outer surface 21 of the base material portion 11, and the step 40 is built up. A part of the built-up portion 14 can be scraped off together with the built-up portion 41. Thereby, the outer side surface 21 of the base material part 11 turns into a surface smoothly connected with the outer side surface 20 of the build-up part 14. FIG. That is, the boundary between the base material portion 11 and the built-up portion 14 is smoothly finished without unevenness. In this way, the gas turbine rotor blade 10 can be repaired without reducing the thickness of the base material portion 11.

(Third embodiment)
FIG. 16 is a diagram illustrating a process of the gas turbine rotor blade repair method according to the third embodiment. As in the case of the gas turbine rotor blade repair method of the first embodiment, in the case of repair of the gas turbine rotor blade 10 that does not have the coating layer 15 on the blade surface, the coating layer removal step S120 and the coating are performed. Processing step S123 is not necessary.

  FIG. 17 is a diagram illustrating a cross-section corresponding to the cross-section AA of FIG. 1 after the wear part removing step of the gas turbine rotor blade repair method according to the third embodiment. 18-20 is a figure which shows the cross section equivalent to the AA cross section of FIG. 1 for demonstrating the blade tip formation process of the repair method of the gas turbine rotor blade of 3rd Embodiment.

  Here, the receiving process, the coating layer removing process S120, and the worn part removing process S121 are the same processes as the receiving process, the coating layer removing process S100, and the worn part removing process S101 in the first embodiment. .

  After the worn part removing step S121 (see FIG. 17), the same shape as the original shape of the blade tip 10a before being worn out is directly formed on the processed flat surface 13 of the blade tip 10a (blade tip forming step S122). .

  Here, the blade tip forming step S122 will be described.

  In the blade tip forming step S122, as shown in FIG. 18, the component member 50 separately formed in advance in the same shape as the shape of the initial blade tip 10a in the portion processed in the wear and wear portion removing step S121 is prepared. , And joined on the plane 13 of the blade tip 10a. The constituent member 50 is made of a material such as a Ni-based heat-resistant alloy such as IN738 (trade name) or GTD111 (trade name).

  The component member 50 is joined on the plane 13 of the blade tip 10a by, for example, TIG welding, brazing, or the like. Here, the brazing alloy has a solidus temperature higher than the solution heat treatment temperature of the substrate.

  For example, in a gas turbine rotor blade having a cooling hole at the blade tip, the cooling hole can be processed in advance in the component member 50, so that complicated cooling holes can be easily processed.

  Further, in the blade tip forming step S122, as shown in FIG. 19, the flesh having the same shape as the shape of the original blade tip 10a before being worn and worn on the flat surface 13 of the blade tip 10a by microspark coating. The raised portion 61 may be formed. In this micro spark coating, the coating layer 60 can be formed on the flat surface 13 of the blade tip 10a by performing electric discharge machining using an electrode containing a material such as Ni-based powder. The build-up portion 61 is formed by laminating the coating layer 60.

  In microspark coating, fine pulsed discharge with a diameter of micron level is locally generated repeatedly and melt-bonded, so that the shrinkage of the base material portion 11 is in a very limited range. Therefore, the deformation of the base material portion 11 can be suppressed to an extremely small level. Moreover, since the coating layer 60 is melt-bonded, it does not peel off.

  Further, in the blade tip forming step S122, as shown in FIG. 20, a forming die 70 having the same shape as the shape of the original blade tip 10a before being worn is installed. Then, build-up welding may be performed inside the mold 70 to form the build-up portion 14 having the same shape as the original shape of the blade tip 10a before being worn on the flat surface 13 of the blade tip 10a.

  The build-up welding is the same as the build-up welding in the build-up welding step S102 of the first embodiment, for example. Further, after the blade tip forming step S122, the mold 70 is removed. In order to easily remove the molding die 70 from the build-up portion 14, it is preferable to use a molding die made of a ceramic plate such as high-purity alumina, zirconia, or mullite having poor bondability with the repair material.

  Further, in the blade tip forming step S122, as shown in FIG. 20, a forming die 70 having the same shape as the shape of the original blade tip 10a before being worn is installed. Then, overlaying by brazing may be performed inside the forming die 70 to form a build-up portion having the same shape as the original shape of the blade tip 10a before being worn on the flat surface 13 of the blade tip 10a. . Note that the mold 70 is removed after the blade tip forming step S122.

  Here, the brazing alloy is a ceramic plate such as high-purity alumina, zirconia, or mullite that has a solidus temperature higher than the solution heat treatment temperature of the base material and has poor bondability to the brazing material. Overlaying is performed by filling the manufactured mold.

  It is not necessary to finish the surface after each blade tip forming step S122 described above. Therefore, the thickness of the base material part 11 does not decrease.

  The subsequent coating processing step S123 and heat treatment step S124 are the same processing as the coating processing step S105 and heat treatment step S106 of the first embodiment. The heat-treated gas turbine rotor blade 10 is subjected to a final inspection in the same manner as in the first embodiment.

  Through the above repair process, the gas turbine rotor blade 10 in which the wear of the blade tip 10a is repaired is obtained.

  As described above, according to the gas turbine rotor blade repair method of the third embodiment, the same shape as that of the original blade tip 10a before being worn out is directly formed on the flat surface 13 of the blade tip 10a. can do. Therefore, it is not necessary to finish the surface after the blade tip forming step S122, and the gas turbine rotor blade 10 can be repaired without reducing the thickness of the base material portion 11. In addition, the boundary between the forming part formed in the blade tip forming step S122 and the base material part 11 is smoothly finished without unevenness.

  According to the embodiment described above, the gas turbine rotor blade can be repaired without reducing the thickness of the base material.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 10 ... Gas turbine rotor blade, 10a ... Blade | tip tip, 11 ... Base material part, 12 ... Wear part, 13 ... Plane, 14, 30, 61 ... Overlay part, 15, 60 ... Coating layer, 20, 21 ... Outer surface , 23, 40 ... step, 24 ... outer peripheral end face, 25 ... inner surface, 41 ... base material built-up part, 50 ... constituent member, 70 ... molding die, 110 ... laser torch, 111 ... laser light, 112 ... powder, 113 ... Powder feeder, 114 ... weld bead.

Claims (8)

In the repair method of the gas turbine rotor blade for repairing the blade tip of the gas turbine rotor blade,
A worn part removing step of removing the worn part of the blade tip and processing the blade tip into a flat surface;
Overlay welding is performed on the blade tip processed into a flat surface to form a built-up portion having a predetermined height and a predetermined thickness; and
While processing the front-end | tip part and inner part of the said build-up part to the same shape as the shape of the said wing | blade tip before the wear out, the base material part from which the outer surface of the said build-up part comprises the said wing | tip tip A step forming step for forming a step by processing the build-up portion so as to be on the inner side of the gas turbine rotor blade than the outer surface of
Applying a build-up process to the outer surface of the built-up portion, eliminating the step between the outer surface of the built-up portion and the outer surface of the base material portion, the same shape as the shape of the initial blade tip before wear A step overlaying process, and
A gas turbine rotor blade repair method comprising: a heat treatment step of performing solution heat treatment and aging heat treatment. In the repair method of the gas turbine rotor blade for repairing the blade tip of the gas turbine rotor blade,
A worn part removing step of removing the worn part of the blade tip and processing the blade tip into a flat surface;
Overlay welding is performed on the blade tip processed into a flat surface to form a built-up portion having a predetermined height and a predetermined thickness; and
While processing the front-end | tip part and inner part of the said build-up part to the same shape as the shape of the said wing | blade tip before the wear out, the base material part from which the outer surface of the said build-up part comprises the said wing | tip tip A step forming step of forming the step by processing the build-up portion so as to be on the outer side of the gas turbine rotor blade than the outer surface of
Step build-up process is performed to build up the outer surface of the base material portion, and eliminate the step between the outer surface of the base material portion and the outer surface of the build-up portion,
Processing the base material built-up portion and the built-up portion formed on the outer surface of the base material portion, and forming the outer surface into the same shape as the shape of the initial blade tip before wearing out,
A gas turbine rotor blade repair method comprising: a heat treatment step of performing solution heat treatment and aging heat treatment. In the repair method of the gas turbine rotor blade for repairing the blade tip of the gas turbine rotor blade,
A worn part removing step of removing the worn part of the blade tip and processing the blade tip into a flat surface;
On the processed plane of the blade tip, a blade tip forming step for directly forming the same shape as the shape of the original blade tip before being worn out;
A gas turbine rotor blade repair method comprising: a heat treatment step of performing solution heat treatment and aging heat treatment. In the blade tip forming step,
A component member formed separately in advance in the same shape as the initial shape of the blade tip in the portion processed in the wear and wear portion removing step is joined on the plane of the blade tip. Item 4. A method for repairing a gas turbine rotor blade according to Item 3. In the blade tip forming step,
4. The gas turbine according to claim 3, wherein a build-up portion having the same shape as the shape of the original blade tip before being worn and formed by microspark coating is formed on a plane of the blade tip. How to repair moving blades. In the blade tip forming step,
A mold having the same shape as that of the initial blade tip before wear and tear is placed, and overlay welding is performed inside the mold, and the shape of the initial blade tip is formed on the plane of the blade tip. 4. The method for repairing a gas turbine rotor blade according to claim 3, wherein a built-up portion having the same shape is formed. In the case where a coating layer is formed on the blade surface of the gas turbine rotor blade,
Before the worn part removing step, a coating layer removing step for removing the coating layer;
The gas turbine rotor blade according to any one of claims 1 to 6, further comprising a coating process step of forming a coating layer on a blade surface of the gas turbine rotor blade immediately before the heat treatment step. Repair method.   A gas turbine rotor blade repaired by the gas turbine rotor blade repair method according to any one of claims 1 to 7.

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