JP6856426B2 - Thermal barrier coating method, wing segment manufacturing method - Google Patents

Description

The present invention relates to a method thermal barrier coating, relates to the method of manufacturing the vane segment.

In the gas turbine, the temperature of the gas used is set high in order to improve its efficiency. A thermal barrier coating (TBC) is applied to the surface of a turbine member such as a moving blade or a stationary blade exposed to such a high temperature gas. The heat shield coating is a coating on the surface of a turbine member, which is an object to be sprayed, with a thermal spray material having a low thermal conductivity (for example, a ceramic material having a low thermal conductivity) by thermal spraying. By forming the heat-shielding coating on the surface of the turbine member, the heat-shielding property and durability of the turbine member are improved. The thermal barrier coating is formed by spraying sprayed particles from the outside of the turbine member toward the surface of the turbine member with a spray gun.

Patent Document 1 describes a heat shield coating formed on the surface of a rotor blade. The heat shield coating has a bond coat layer which is a first film formed on the base material and a dense top coat layer which is a second film formed on the bond coat layer and has vertical cracks. ing. The topcoat layer is formed by a method such as atmospheric plasma spraying (APS) method.

Japanese Unexamined Patent Publication No. 2008-174838

By the way, as a turbine member on which a heat shield coating is formed, there is a stationary blade segment in which a plurality of blade bodies are integrally formed on one shroud. In the stationary wing segment, the distance between adjacent wing bodies is narrow. As a result, on the opposing surfaces of the wing body, there is an area that is shaded when viewed from the outside of the stationary wing segment. Even if sprayed particles are sprayed from the outside of the stationary blade segment to form a topcoat layer on this shaded area, the sprayed particles do not spread to the shaded area, and a homogeneous topcoat layer is formed. Is difficult to form. As a result, it may not be possible to form a homogeneous topcoat layer over the entire wing segment with multiple adjacent wing bodies.

The present invention has been made in view of the above circumstances, and is a thermal barrier coating method capable of forming a homogeneous topcoat layer over the entire area of a blade segment having a plurality of adjacent blade bodies, and a method for manufacturing a blade segment. The purpose is to provide.

The present invention employs the following means in order to solve the above problems.
In the thermal spray coating method according to the first aspect of the present invention, a plurality of wing bodies having a cross-sectional wing shape and arranged apart in the wing thickness direction, and the plurality of wing bodies at the base end portion in the wing height direction of the wing body. A heat-shielding coating method for forming a heat-shielding coating on a wing segment body having a wing tip wall portion connecting the wing bodies, wherein the first thermal spray gun is inserted into a space between adjacent wing bodies to insert the wing. The wing facing the narrow space is moved in the first direction intersecting the height direction, and sprayed particles are injected in a narrow space where the distance between the wing bodies is shorter than a predetermined distance in the space. A narrow space top coat layer forming step of forming a top coat layer containing ceramic on the surface of the main body, and a second thermal spray gun larger than the first thermal spray gun are moved in the blade height direction outside the blade segment main body. The first thermal spraying gun includes a gun main body portion extending in the first direction and the gun main body portion, including an entire area top coat layer forming step of forming the top coat layer on the surface of the wing segment main body. provided at the tip, the thermal spraying particles in a direction crossing the first direction possess an injection portion which injection holes are formed for ejecting, in the narrow space topcoat layer forming step, the first spray The gun is moved to a position where the injection portion is removed from the narrow space and the distance between the injection hole of the first thermal spray gun and the surface of the wing body is wider than the predetermined minimum thermal spraying distance, and then the wing height is reached. By moving in the direction, it is reciprocated in the first direction, and the movement speed of the first thermal spray gun in the first direction at a position outside the narrow space is higher than the movement speed in the narrow space. It is said that the speed is too fast for thermal spraying .

According to such a configuration, the sprayed particles are sprayed onto the narrow surface from the injection hole of the first spray gun facing the surface of the blade body facing the narrow space. As a result, a sufficient amount of sprayed particles is formed on the surface of the wing body facing the narrow space where the amount of sprayed particles that can form a uniform topcoat layer is not distributed because the sprayed particles are shaded from the outside of the blade segment. Can be sprayed. Further, in the blade body having a complicated shape having a three-dimensional curved surface, the surface of the blade body facing the narrow space has a complicated curved surface shape in the blade height direction and extends long. On the other hand, the surface of the wing body facing the narrow space has a simple curved surface shape in the chord direction and extends shortly. Therefore, if the first sprayed portion is moved in the blade height direction along the surface of the blade body facing the narrow space, it is difficult to keep the distance of the injection portion constant with respect to the surface of the blade body facing the narrow space. On the other hand, by moving the first thermal spray gun in the first direction, it becomes easier to stabilize the position of the injection portion with respect to the surface of the blade body facing the narrow space, as compared with the case of moving it in the blade height direction. As a result, the sprayed particles can be sprayed by arranging the injection holes at an angle close to perpendicular to the surface of the blade body facing the narrow space. As a result, the sprayed particles can be uniformly sprayed onto the surface of the blade body facing the narrow space.

Further , when the first thermal spray gun is reciprocated in the chord direction, the first thermal spray gun is moved in the blade height direction at a position where the injection portion is out of the narrow space. Therefore, it is possible to prevent the first spraying gun from being moved in the blade height direction while the sprayed particles are sprayed on the surface of the blade body facing the narrow space. As a result, it is suppressed that the sprayed particles are sprayed onto the narrow surface in a state where the distance of the injection portion to the surface of the blade body facing the narrow space varies. Therefore, it is possible to prevent the formation of a non-uniform top coat layer in the blade height direction with respect to the surface of the blade body facing the narrow space.

Furthermore , by increasing the moving speed of the first spraying gun at a position outside the narrow space, the sprayed particles sprayed from the first spraying gun can be sprayed on the surface of the wing body other than the surface of the wing body facing the narrow space. It becomes difficult to adhere. Therefore, it is possible to prevent the first thermal spray gun from locally depositing thermal spray particles on the surface of the blade body outside the narrow space.

Further, in the second according to the embodiment thermal barrier coating method of the present invention, Oite to a first aspect, in the narrow space topcoat layer forming step, the top coat layer has been formed against the dorsal surface of the blade body You may.

With such a configuration, the surface of the wing body facing the narrow space is regarded as the back side surface of the wing body. Therefore, the first thermal spray gun is inserted into the narrow space with the injection hole facing the back side surface. As a result, the top coat layer can be formed with high accuracy on the back side surface, which tends to be shaded from the outside, among the surfaces of the wing body facing the narrow space.

Further, in the third according to the embodiment thermal barrier coating method of the present invention, Oite the first or second aspect, the entire top coat layer forming step, be performed after the narrow space topcoat layer forming step Good.

With such a configuration, it is possible to prevent the sprayed particles from being locally deposited on the surface of the blade body facing the narrow space.

Further, in the heat shield coating method according to the fourth aspect of the present invention, in any one of the first to third aspects, the injection portion is inclined from the gun body portion toward the injection direction of the sprayed particles. May be extended.

With such a configuration, the injection portion is inclined along the surface of the blade body with respect to the extending direction of the gun body. Therefore, when the injection portion is inserted into the space, the injection portion can reach a deeper position without contacting the injection portion with the curved surface of the blade body. As a result, the injection portion can reach the narrow space without interfering with the first thermal spray gun with the blade body. As a result, the distance between the injection portion and the narrow surface in the narrow space can be set as an appropriate spraying distance. By spraying on a narrow surface with an appropriate spraying distance, a topcoat layer with the required performance can be formed on the surface of the blade body facing the narrow space.

Further, in the heat shield coating method according to the fifth aspect of the present invention, in any one of the first to fourth aspects, it is carried out before the narrow space top coat layer forming step, and the first aspect is formed in the space. A narrow space in which a thermal spray gun is inserted and moved in the first direction, and thermal spray particles are ejected in the narrow space to form an undercoat layer as a metal bonding layer on the surface of the wing body facing the narrow space. An undercoat layer forming step may be further included.

With such a configuration, a homogeneous undercoat layer can be formed on the surface of the blade body facing the narrow space. As a result, a topcoat layer can be formed on a homogeneous undercoat layer on the surface of the blade body facing the narrow space. As a result, the adhesion of the top coat layer on the surface of the wing body facing the narrow space can be improved.

Further, in the heat shield coating method according to the sixth aspect of the present invention, in the fifth aspect, the sprayed particles are ejected from the outside of the blade segment body by being carried out before the narrow space undercoat layer forming step. The entire area undercoat layer forming step of forming the undercoat layer on the surface of the blade segment main body may be further included.

Further, in the heat shield coating method according to the seventh aspect of the present invention, in any one of the first to sixth aspects, in the narrow space top coat layer forming step, the narrow space is based on the shape of the blade body. The space may be specified in advance, and the thermal spraying conditions by the first thermal spraying gun may be changed and controlled according to the thermal spraying position.

With such a configuration, the top coat layer can be formed on the surface of the blade body facing the narrow space and the surface of the blade body other than that under appropriate spraying conditions. Therefore, a higher quality topcoat layer can be formed on the surface of the blade body.

Further, in the method for manufacturing a blade segment according to the eighth aspect of the present invention, a plurality of blade bodies having a cross-sectional blade shape and arranged apart in the blade thickness direction and a base end portion of the blade body in the blade height direction are used. The wing segment is prepared by a wing segment main body preparation step of preparing a wing segment main body having a wing tip wall portion connecting the plurality of wing main bodies, and a heat shield coating method according to any one of the first to seventh aspects. It includes a heat shield coating forming step of forming the top coat layer on the surface of the blade main body facing the narrow space of the blade segment main body prepared in the main body preparation step.

According to the present invention, a homogeneous topcoat layer can be formed over the entire area of a blade segment having a plurality of adjacent blade bodies.

It is a perspective view explaining the stationary wing segment which concerns on embodiment of this invention. It is a schematic diagram explaining the thermal barrier coating which concerns on embodiment of this invention. It is a flow figure explaining the manufacturing method of the wing segment which concerns on embodiment of this invention. It is sectional drawing of the blade segment explaining the state which the 1st thermal spray nozzle is inserted in the narrow space which concerns on embodiment of this invention. It is a side view of the blade segment explaining the moving state of the 1st thermal spray nozzle which concerns on embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 5.
The blade segment manufacturing method S1 manufactures a blade segment on which a heat shield coating is formed. In the blade segment manufacturing method S1 of the present embodiment, the stationary blade segment 1 of the gas turbine is manufactured as the blade segment. The vane segments 1 are arranged in an annular shape and connected to each other to form one vane ring. The stationary blade segment 1 has a blade segment main body 2 and a heat shield coating 3.

The blade segment main body 2 is formed of, for example, a well-known heat-resistant alloy such as a Ni-based alloy. As shown in FIG. 1, the wing segment main body 2 has a wing main body 21, an inner shroud (blade tip wall portion) 22, and an outer shroud 23.

The blade body 21 has a blade-shaped cross section and extends in the blade height direction Dx. The blade body 21 extends in the radial direction of the rotor (not shown) of the gas turbine. Therefore, the blade height direction Dx in which the blade body 21 extends is the radial direction of the rotor. The dorsal side surface 21a (see FIG. 4), which is the dorsal surface of the wing body 21, is a convex surface when viewed from the blade height direction Dx. The wing body 21 has a concave surface on the ventral side surface 21b (see FIG. 4), which is the ventral surface when viewed from the wing height direction Dx. In the wing body 21, the front end portion on the front side in the chord direction Dy forms the front edge portion 21c. In the blade body 21, the rear end portion in the chord direction Dy forms the trailing edge portion 21d. A plurality of blade main bodies 21 (three in the present embodiment) are lined up apart from each other in the blade thickness direction Dz. A space A is formed between the adjacent wing bodies 21.

Here, the blade height direction Dx of the blade body 21 is the direction in which the blade body 21 extends. Further, the chord direction Dy of the wing body 21 is a direction orthogonal to the wing height direction Dx in the present embodiment, and includes the front edge portion 21c and the trailing edge portion 21d including the extending direction of the wing chord of the wing body 21. The direction should be parallel to the virtual line connecting. The blade thickness direction Dz of the blade body 21 is a direction orthogonal to the blade height direction Dx and the blade chord direction Dy in the present embodiment.

The inner shroud 22 connects a plurality of blade bodies 21 on the base end side in the blade height direction Dx. The inner shroud 22 of the present embodiment has a parallel quadrilateral shape when viewed from the blade height direction Dx. The inner shroud 22 is formed so that the length of the blade thickness direction Dz is longer than the length of the chord chord direction Dy.

The outer shroud 23 connects a plurality of blade bodies 21 on the tip end side (outer shroud 23 side) in the blade height direction Dx. Therefore, the outer shroud 23 is arranged on the side opposite to the inner shroud 22 in the blade height direction Dx with the blade body 21 interposed therebetween. The outer shroud 23 of the present embodiment has a parallel quadrilateral shape when viewed from the blade height direction Dx. The inner shroud 22 is formed so that the length of the blade thickness direction Dz is longer than the length of the chord chord direction Dy.

In the blade segment main body 2, a space A defined by an adjacent blade main body 21, an inner shroud 22, and an outer shroud 23 is formed as a flow path through which combustion gas in a gas turbine flows. The space A of the wing segment main body 2 includes a narrow space Ax in which the distance between adjacent wing main bodies 21 is shorter than a predetermined distance. Therefore, in the space A, the distance in the blade thickness direction Dz changes toward the chord direction Dy according to the shape of the blade body 21. Here, the narrow space Ax is an area in the space A in which the distance in the blade thickness direction Dz is equal to or less than the distance at which the second thermal spray gun, which will be described later, cannot be inserted. Therefore, the predetermined distance of the present embodiment is, for example, the size of the outer diameter of the second thermal spray gun. As shown in FIG. 4, the narrow space Ax of the present embodiment is formed so as to face the back side surface 21a on the front edge portion 21c side of the center position of the wing body 21 in the chord direction Dy. The narrow space Ax extends from the base end side (inner shroud 22 side) of the blade body 21 in the blade height direction Dx to the tip end side.

The heat shield coating 3 is formed on the surface of the blade segment main body 2 using the blade segment main body 2 as a base material. The heat shield coating 3 is formed so as to cover the entire surface of the blade segment main body 2. As shown in FIG. 2, the heat shield coating 3 has an undercoat layer 31 and a topcoat layer 32.

The undercoat layer 31 suppresses the topcoat layer 32 from peeling off from the blade segment main body 2. The undercoat layer 31 is a metal bonding layer having excellent corrosion resistance and oxidation resistance. The undercoat layer 31 is formed by spraying, for example, a metal spray powder of an MCRALY alloy as a spray material onto the surface of the blade segment main body 2. Here, "M" of the MCrAlY alloy constituting the undercoat layer 31 indicates a metal element. The metal element "M" is composed of, for example, a single metal element such as NiCo, CoNi, Ni, Co, or a combination of two or more of these.

The top coat layer 32 is laminated on the surface of the undercoat layer 31. The top coat layer 32 is formed by spraying a thermal spray material containing ceramic onto the surface of the undercoat layer 31. The top coat layer 32 of the present embodiment is a DVC (Dense Virtualy Crack) film which is a ceramic film having a fine vertical division, a porous film having pores, or the like. As the thermal spray material used when forming the top coat layer 32, a zirconia-based ceramic can be used. Examples of the zirconia-based ceramic include yttria-stabilized zirconia (YSZ) and ytterbium-stabilized zirconia (YbSZ), which is zirconia (ZrO _{2 ) partially stabilized with ytterbium oxide (Yb 2} O _3).

Next, a method S1 for manufacturing a blade segment for manufacturing the above-mentioned stationary blade segment 1 will be described. As shown in FIG. 3, the blade segment manufacturing method S1 of the present embodiment includes a blade segment main body preparation step S10 and a heat shield coating forming step S20.

In the wing segment main body preparation step S10, the wing segment main body 2 is prepared in advance. In the blade segment main body preparation step S10 of the present embodiment, the blade segment main body 2 is manufactured and prepared by casting or the like.

In the heat shield coating forming step S20, the heat shield coating 3 is formed on the surface of the blade segment body 2 prepared in the blade segment body preparation step S10 by the heat shield coating method S30. In the heat shield coating forming step S20 of the present embodiment, the undercoat layer 31 and the topcoat layer 32 are formed on the surface of the blade segment main body 2. In the heat shield coating forming step S20, the undercoat layer 31 and the topcoat layer 32 are also formed on the surface of the blade body 21 facing the narrow space Ax in the space A of the blade segment body 2. The heat shield coating forming step S20 of the present embodiment is carried out by the following heat shield coating method S30.

In the heat shield coating method S30, the heat shield coating 3 is formed on the blade segment main body 2. The heat shield coating method S30 of the present embodiment includes an entire area undercoat layer forming step S31, a narrow space undercoat layer forming step S32, a narrow space topcoat layer forming step S33, and an entire area topcoat layer forming step S34. .. In the heat shield coating method S30 of the present embodiment, the first thermal spray gun 5 is used when spraying the narrow surface X, which is the surface of the blade body 21 facing the narrow space Ax. Further, when the wing segment main body 2 is sprayed from the outside, a second thermal spray gun is used. The narrow surface X of this embodiment is as shown in FIG. Of the opposing surfaces of the adjacent wing bodies 21, the back side surface 21a of the wing body 21 on one side. The narrow surface X is formed on the front edge portion 21c side of the center position of the wing body 21 in the chord direction Dy. As shown in FIG. 5, the narrow surface X extends from the base end side to the tip end side of the blade body 21 in the blade height direction Dx.

The first thermal spray gun 5 has a smaller power output and a smaller amount of powder to be supplied than the second thermal spray gun. When atmospheric spraying (APS: atmospheric plasma spraying) is performed on the first thermal spray gun 5, the film formation width of one pass is about 10 mm to 1 mm. As shown in FIG. 4, the first thermal spray gun 5 has a gun main body portion 51 and an injection portion 52.

The gun main body 51 extends in the first direction, which is the moving direction of the first thermal spray gun 5. The gun body 51 of the present embodiment has a columnar shape. The first direction is the direction in which the gun main body 51 extends and intersects the blade height direction Dx. The first direction of this embodiment is the chord direction Dy.

The injection portion 52 is integrally provided at the tip of the gun main body portion 51. The injection unit 52 is formed with an injection hole 53 for injecting sprayed particles in a direction intersecting the first direction. The injection hole 53 of the present embodiment is opened in a direction orthogonal to the extending direction of the gun main body 51. The injection unit 52 of the present embodiment extends from the gun main body 51 so as to be inclined toward the injection direction of the sprayed particles. Therefore, the first thermal spray gun 5 of the present embodiment is formed so as to be bent by the injection portion 52 forming the tip portion in the extending direction of the gun main body portion 51. Specifically, the injection unit 52 is inclined by about 5 ° to 20 ° with respect to the extending direction of the gun main body 51, and it is particularly preferable that the injection unit 52 is inclined by about 10 °. The inclination angle of the injection unit 52 may be appropriately set according to the shape of the blade body 21.

The second thermal spray gun has a larger outer shape than the first thermal spray gun 5. The second thermal spray gun has a larger output and the amount of powder supplied than the first thermal spray gun 5. When the atmospheric plasma spraying method is carried out, the second thermal spray gun has a one-pass film formation width of about 15 mm to 25 mm. The second thermal spray gun has a columnar shape. The second thermal spray gun injects thermal spray particles in a direction extending from the tip portion. The second thermal spray gun is formed with a cross-sectional shape having a size that cannot be inserted into the space A.

As shown in FIG. 3, the entire area undercoat layer forming step S31 is carried out before the narrow space undercoat layer forming step S32. In the entire area undercoat layer forming step S31, the sprayed particles are sprayed from the outside of the blade segment main body 2 to form the undercoat layer 31 on the surface of the blade segment main body 2. In the entire area undercoat layer forming step S31 of the present embodiment, the undercoat layer 31 is subjected to high-speed frame thermal spraying (HVOF: High Velocity Oxygen Fuel) or reduced pressure plasma spraying (LPPS: Low Pressure Plasma Spraying) with a second thermal spray gun. To form. In the entire area undercoat layer forming step S31, the spraying gun for HVOF or LPPS that sprays the sprayed particles is reciprocated outside the blade segment main body 2 in the blade height direction Dx.

The narrow space undercoat layer forming step S32 is performed before the narrow space topcoat layer forming step S33. In the narrow space undercoat layer forming step S32, the undercoat layer 31 as a metal bonding layer is formed on the narrow surface X which is the surface of the blade body 21 facing the narrow space Ax by using the first thermal spray gun 5. In the narrow space undercoat layer forming step S32, the sprayed particles are sprayed from the first spray gun 5 in the narrow space Ax. In the narrow space undercoat layer forming step S32, the first thermal spray gun 5 is inserted into the space A from the trailing edge portion 21d side as shown in FIG. After that, the first thermal spray gun 5 is moved toward the front edge portion 21c in the chord direction Dy, which is the first direction.

In the narrow space undercoat layer forming step S32 of the present embodiment, the first thermal spray gun 5 is inserted into the space A with the injection hole 53 facing the back side surface 21a of the wing body 21. As a result, in the narrow space undercoat layer forming step S32, the undercoat layer 31 is formed only on the back side surface 21a in the narrow space Ax.

In the narrow space undercoat layer forming step S32, as shown in FIG. 5, the first spraying gun 5 that sprays the sprayed particles is reciprocated in the chord direction Dy. When the first thermal spray gun 5 is reciprocated, the position of the injection portion 52 is moved in the blade height direction Dx at a position deviated from the narrow space Ax when viewed from the blade thickness direction Dz. Specifically, in the first thermal spray gun 5, on the trailing edge portion 21d side, when viewed from the blade thickness direction Dz, the injection portion 52 moves to a position deviated from the blade body 21 and then the blade height direction Dx. Moved to the tip side. Further, on the front edge portion 21c side of the first thermal spray gun 5, the distance between the injection hole 53 and the surface of the blade main body 21 becomes wider than the predetermined minimum thermal spray distance when viewed from the blade thickness direction Dz. After the injection portion 52 has moved to, it is moved to the tip end side in the blade height direction Dx.

At this time, the moving speed of the first thermal spray gun 5 at a position outside the narrow space Ax is faster than the moving speed in the narrow space Ax. In the first thermal spray gun 5, it is preferable that the moving speed of the chord direction Dy when the injection portion 52 exists at a position outside the narrow space Ax is a speed at which film formation cannot be performed. On the contrary, in the first thermal spray gun 5, it is preferable that the moving speed of the chord direction Dy when the injection portion 52 exists in the narrow space Ax is a speed at which a film can be formed uniformly.

Here, the specific spraying conditions in the narrow space undercoat layer forming step S32 are, for example, the spraying material is sprayed particles of MCrAlY alloy, Ar / H2 is 50/2 [l / min], and the current value is 260 [A]. ], The amount of powder may be 4 [g / min], and the spraying distance may be 25 [mm].

In the narrow space top coat layer forming step S33, the top coat layer 32 containing ceramic is formed on the narrow surface X by thermal spraying using the first thermal spray gun 5. Therefore, in the narrow space top coat layer forming step S33 of the present embodiment, the top coat layer 32 is formed on the narrow surface X on which the undercoat layer 31 is formed. In the narrow space top coat layer forming step S33, the sprayed particles are ejected in the narrow space Ax. The narrow space top coat layer forming step S33 is different from the narrow space undercoat layer forming step S32 in that the sprayed particles are used, and the first spraying gun 5 is moved in the same motion as the narrow space undercoat layer forming step S32. Spray.

Specifically, in the narrow space top coat layer forming step S33 of the present embodiment, the first thermal spray gun 5 is inserted into the space A from the trailing edge portion 21d side as shown in FIG. After that, the first thermal spray gun 5 is moved toward the front edge portion 21c in the chord direction Dy. At that time, the injection hole 53 of the first thermal spray gun 5 faces the back side surface 21a of the blade body 21. As a result, in the narrow space top coat layer forming step S33, the top coat layer 32 is formed only on the back side surface 21a in the narrow space Ax.

In the narrow space top coat layer forming step S33, as shown in FIG. 5, the first spraying gun 5 that sprays the sprayed particles is reciprocated in the chord direction Dy. When the first thermal spray gun 5 is reciprocated, it is moved in the blade height direction Dx at a position where the injection portion 52 is separated from the narrow space Ax. Specifically, in the first thermal spray gun 5, on the trailing edge portion 21d side, when viewed from the blade thickness direction Dz, the injection portion 52 moves to a position deviated from the blade body 21 and then the blade height direction Dx. Moved to the tip side. Further, on the front edge portion 21c side of the first thermal spray gun 5, the distance between the injection hole 53 and the surface of the blade main body 21 is predetermined and wider than the minimum thermal spray distance when viewed from the blade thickness direction Dz. After the injection portion 52 has moved to, it is moved to the tip end side in the blade height direction Dx.

At this time, the moving speed of the first thermal spray gun 5 at a position outside the narrow space Ax is faster than the moving speed in the narrow space Ax. In the first thermal spray gun 5, it is preferable that the moving speed of the chord direction Dy when the injection portion 52 exists at a position outside the narrow space Ax is a speed at which film formation cannot be performed. On the contrary, in the first thermal spray gun 5, it is preferable that the moving speed of the chord direction Dy when the injection portion 52 exists in the narrow space Ax is a speed capable of forming a uniform film.

Further, in the narrow space top coat layer forming step S33, the narrow space Ax is specified in advance based on the shape of the blade body 21, and the thermal spraying condition by the first thermal spray gun 5 is changed and controlled according to the thermal spraying position. Specifically, in the narrow space top coat layer forming step S33, a simulation is performed in advance to specify the shape of the narrow space Ax based on the shape of the blade body 21. It is controlled to change the spraying conditions such as the position and moving speed of the first spraying gun 5 and the amount of powder of the sprayed particles to be sprayed according to the shape of the specified narrow space Ax.

Here, the spraying conditions in the narrow space top coat layer forming step S33 are, for example, a sprayed material of YSZ sprayed particles, Ar / H2 of 30 / 2.5 [l / min], and a current value of 250 [A]. The amount of powder may be 15 [g / min] and the spraying distance may be 21 to 29 [mm].

The whole area top coat layer forming step S34 is carried out after the narrow space top coat layer forming step S33. In the entire area topcoat layer forming step S34, the topcoat layer 32 is formed over the entire surface of the blade segment main body 2 by atmospheric plasma spraying using a second thermal spray gun. In the entire area top coat layer forming step S34, the second thermal spray gun is reciprocated outside the blade segment main body 2 in the blade height direction Dx.

Here, the thermal spraying conditions in the entire area topcoat layer forming step S34 are, for example, the thermal spraying material is YSZ sprayed particles, Ar / H2 is 35 / 7.4 [l / min], the current value is 600 [A], and the powder. The amount is 60 [g / min] and the spraying distance is 180 to 250 [mm].

According to the heat shield coating method S30 as described above, in the narrow space undercoat layer forming step S32 and the narrow space topcoat layer forming step S33, the first thermal spray gun 5 is inserted into the narrow space Ax. The first thermal spray gun 5 has an injection hole 53 that opens in a direction orthogonal to the extending direction of the gun main body 51. As a result, by performing atmospheric plasma spraying with the first thermal spray gun 5, the thermal spray particles are directly sprayed onto the narrow surface X from the injection hole 53 facing the narrow surface X. As a result, a sufficient amount of sprayed particles can be sprayed onto the narrow surface X where the amount of sprayed particles that can form a homogeneous topcoat layer 32 is not distributed, which is shaded from the outside of the stationary blade segment 1.

Further, in the narrow space undercoat layer forming step S32 and the narrow space topcoat layer forming step S33, the first thermal spray gun 5 reciprocates in the chord direction Dy instead of the blade height direction Dx. In the blade body 21 having a complicated shape having a three-dimensional curved surface, the narrow surface X has a complicated curved surface shape in the blade height direction Dx and extends long. On the other hand, the narrow surface X has a simple curved surface shape and extends shortly in the chord direction Dy. Therefore, when the first sprayed portion is moved in the blade height direction Dx along the narrow surface X, it is difficult to keep the distance of the injection portion 52 constant with respect to the surface of the blade body 21 facing the narrow space Ax. On the other hand, by moving the first thermal spray gun 5 in the chord direction Dy, it becomes easier to stabilize the position of the injection portion 52 with respect to the narrow surface X as compared with the case where it is moved in the blade height direction Dx. As a result, the sprayed particles can be sprayed by arranging the injection holes 53 at an angle close to perpendicular to the narrow surface X. Therefore, the sprayed particles can be sprayed uniformly on the narrow surface X.

As a result, a sufficient amount of sprayed particles can be uniformly sprayed onto the narrow surface X. After that, in the entire area topcoat layer forming step S34, the topcoat layer 32 and the undercoat layer 31 are formed as usual on the surface of the blade segment main body 2 other than the narrow surface X. Therefore, a homogeneous topcoat layer 32 and an undercoat layer 31 can be formed over the entire area of the stationary blade segment 1 having a plurality of adjacent blade bodies 21.

Further, when the first thermal spray gun 5 is reciprocated in the blade chord direction Dy, the first thermal spray gun 5 is moved in the blade height direction Dx at a position where the injection portion 52 is out of the narrow space Ax. Therefore, it is possible to prevent the first spraying gun 5 from being moved in the blade height direction Dx while the sprayed particles are sprayed on the narrow surface X. As a result, it is pushed that the sprayed particles are sprayed onto the narrow surface X in a state where the distance of the injection unit 52 with respect to the narrow surface X varies. Therefore, it is possible to prevent the formation of the top coat layer 32 and the undercoat layer 31 that are non-uniform in the blade height direction Dx with respect to the narrow surface X.

Further, the moving speed when the injection unit 52 is removed from the narrow space Ax is faster than the moving speed of the first thermal spray gun 5 when the injection unit 52 is located in the narrow space Ax. By increasing the moving speed of the first spraying gun 5 with the injection portion 52 detached from the narrow space Ax, the sprayed particles sprayed from the first spraying gun 5 can be generated on the surface of the blade body 21 other than the narrow surface X. It becomes difficult to adhere. Therefore, it is possible to prevent the first thermal spray gun 5 from locally depositing thermal spray particles on the surface of the blade body 21 that is out of the narrow space Ax.

Further, since the narrow surface X is the back side surface 21a of the blade body 21, the first thermal spray gun 5 is inserted into the narrow space Ax with the injection hole 53 facing the back side surface 21a. As a result, the topcoat layer 32 and the undercoat layer 31 can be formed with high accuracy on the back side surface 21a, which tends to be shaded from the outside, among the surfaces of the wing body 21 facing the narrow space Ax.

Further, in the present embodiment, the entire area topcoat layer forming step S34 is carried out after the narrow space topcoat layer forming step S33. As a result, it is possible to prevent the sprayed particles from being locally deposited on the narrow surface X. Specifically, if the entire area topcoat layer forming step S34 for spraying the sprayed particles by atmospheric plasma spraying is performed first, the sprayed particles sprayed from the second spraying gun when spraying other parts will bounce off. By grazing or grazing, it partially adheres to the narrow surface X as well. This is caused by spraying from a second spraying gun, which has a wider film formation path than the first spraying gun 5 and a large output and supply powder amount, so that high-speed sprayed particles are sprayed over a wide range. .. The sprayed particles unintentionally deposited on the narrow surface X by bouncing or grazing have a poor spraying angle, an insufficient velocity, a low temperature, and the like, so that the adhesion is lowered. As a result, sprayed particles having low adhesion are deposited on the narrow surface X over multiple layers, and the thickness and density of the topcoat layer 32 vary.

On the other hand, by first performing the narrow space top coat layer forming step S33, the first thermal spray gun 5 has a narrower film formation path than the second thermal spray gun, and the output used and the amount of powder supplied are small, and the top coat is applied to the narrow surface X. Layer 32 is formed. At this time, since the first spraying gun 5 sprays the sprayed particles in the narrow space Ax, the sprayed particles are scattered only in a very limited region including the narrow surface X. As a result, not only the non-homogeneous top coat layer 32 is formed on the narrow surface X, but also the non-homogeneous top coat layer 32 is formed on the surface of the blade body 21 other than the narrow surface X. It is possible to prevent it from being stored. As a result, it is possible to prevent variations in the thickness and density of the top coat layer 32 on the surface of the blade body 21 including the narrow surface X.

Further, by forming the uniform topcoat layer 32 on the narrow surface X first, even if the second spraying gun is used later for spraying, the sprayed particles having low adhesion are deposited on the surface of the uniform topcoat layer 32. .. Therefore, it can be removed later by polishing or the like in the next step, and is substantially unaffected when the heat shield coating 3 is formed.

Further, the injection portion 52 of the first thermal spray gun 5 is inclined along the back side surface 21a with respect to the extending direction of the gun main body portion 51. Therefore, when the injection unit 52 is inserted into the space A from the trailing edge side, the injection unit 52 can reach a deeper position without contacting the injection hole 53 with the curved back side surface 21a. As a result, the injection unit 52 can reach the narrow space Ax without interfering with the first thermal spray gun 5 with the blade body 21. As a result, the distance between the injection portion 52 and the narrow surface X in the narrow space Ax can be set as an appropriate thermal spraying distance. If the thermal spraying distance is shortened, the film formed becomes too dense and the thermal conductivity decreases. On the contrary, when the spraying distance is long, the formed film becomes too porous and the durability is lowered. On the other hand, by securing an appropriate spraying distance and spraying on the narrow surface X, the undercoat layer 31 and the topcoat layer 32 having the required performance can be formed on the narrow surface X.

Further, the narrow space undercoat layer forming step S32 is performed before the narrow space top coat layer forming step S33. Therefore, a homogeneous undercoat layer 31 can be formed on the narrow surface X. As a result, the topcoat layer 32 can be formed on the homogeneous undercoat layer 31 on the narrow surface X. As a result, the adhesion of the top coat layer 32 on the narrow surface X can be improved.

Further, in the narrow space top coat layer forming step S33, the spraying conditions such as the position and moving speed of the first spraying gun 5 and the amount of powder of the sprayed particles to be sprayed are adjusted based on the narrow space Ax specified in advance. As a result, the top coat layer 32 can be formed on the narrow surface X and the surface of the blade body 21 other than the narrow surface X under appropriate thermal spraying conditions. Therefore, a higher quality topcoat layer 32 can be formed on the surface of the blade body 21.

(Other variants of the embodiment)
Although the embodiments of the present invention have been described in detail with reference to the drawings, the configurations and combinations thereof in the respective embodiments are examples, and the configurations are added or omitted within the range not deviating from the gist of the present invention. , Replacement, and other changes are possible. Further, the present invention is not limited to the embodiments, but only to the scope of claims.

In the heat shield coating method S30 of the present embodiment, the narrow space undercoat layer forming step S32 may not be performed. Therefore, in the heat shield coating method S30 of the present embodiment, the undercoat layer 31 may be formed by another method.

Moreover, the thermal spraying conditions mentioned in each step are examples, and are not limited. The thermal spraying conditions may be appropriately set according to the apparatus used, the type of thermal spraying particles to be targeted, and the like.

Further, the first direction is not limited to the chord direction Dy, and may be a direction that intersects the blade height direction Dx. The first direction may be a direction along the surface of the blade body 21. In particular, the first direction is preferably the direction along the dorsal side surface 21a.

Further, in the present embodiment, in the narrow space top coat layer forming step S33, the narrow space Ax is specified in advance, and the thermal spraying conditions by the first thermal spray gun 5 are changed and controlled according to the thermal spraying position, but the undercoat layer 31 is formed. The same fixing may be performed at the same time. Therefore, in the narrow space undercoat layer forming step S32, the narrow space Ax may be specified in advance, and the thermal spraying conditions by the first thermal spray gun 5 may be changed and controlled according to the thermal spraying position.

S1 ... Wing segment manufacturing method 1 ... Static wing segment 2 ... Wing segment body 21 ... Wing body Dx ... Wing height direction D ... Wing chord direction Dz ... Wing thickness direction 21a ... Dorsal side surface 21b ... Ventral side surface 21c ... Front edge 21d ... Trailing edge A ... Space 22 ... Inner shroud 23 ... Outer shroud Ax ... Narrow space X ... Narrow surface 3 ... Heat shield coating 31 ... Undercoat layer 32 ... Top coat layer S10 ... Wing segment body preparation process S20 ... Heat shield Coating forming process S30 ... Thermal barrier coating method 5 ... First spray gun 51 ... Gun body 52 ... Injection part 53 ... Injection hole S31 ... Whole area undercoat layer forming process S32 ... Narrow space Undercoat layer forming process S33 ... Narrow space top Coat layer forming step S34 ... Whole area top coat layer forming step

Claims (8)

A wing segment having a plurality of wing bodies arranged in a cross-sectional wing shape and separated from each other in the wing thickness direction, and a wing tip wall portion connecting the plurality of wing bodies at a base end portion in the wing height direction of the wing body. It is a heat shield coating method that forms a heat shield coating on the main body.
The first thermal spray gun is inserted into the space between the adjacent wing bodies and moved in the first direction intersecting the wing height direction, and the distance between the wing bodies in the space is greater than a predetermined distance. A narrow space topcoat layer forming step of injecting thermal spray particles in a short narrow space to form a topcoat layer containing ceramic on the surface of the wing body facing the narrow space.
An entire area topcoat layer forming step in which a second thermal spray gun larger than the first thermal spray gun is moved outside the blade segment body in the blade height direction to form the topcoat layer on the surface of the blade segment body. Including and
The first thermal spray gun
The gun body extending in the first direction and
Wherein provided at the tip of the gun main body, it has a said injection unit injection hole for injecting the spray particles in the direction is formed crossing the first direction,
In the narrow space top coat layer forming step,
After the injection portion is removed from the narrow space and the first spray gun is moved to a position where the distance between the injection hole of the first spray gun and the surface of the blade body becomes wider than the predetermined minimum spray distance. By moving in the blade height direction, it is reciprocated in the first direction,
The moving speed of the first spray gun to said first direction at a position deviated from the narrow space, the narrow space at a high deposition non speed and by that the thermal barrier coating methods than the moving speed of the. The heat shield coating method according to claim 1 , wherein in the narrow space top coat layer forming step, the top coat layer is formed on the back side surface of the blade body. The heat shield coating method according to claim 1 or 2 , wherein the entire area top coat layer forming step is carried out after the narrow space top coat layer forming step. The heat-shielding coating method according to any one of claims 1 to 3 , wherein the injection portion extends from the gun main body portion so as to be inclined toward the injection direction of the sprayed particles. It is carried out before the step of forming the top coat layer in the narrow space, the first spray gun is inserted into the space and moved in the first direction, and the sprayed particles are ejected in the narrow space to surface the narrow space. The heat-shielding coating method according to any one of claims 1 to 4 , further comprising a narrow space undercoat layer forming step of forming an undercoat layer as a metal bonding layer on the surface of the wing body. An entire area undercoat layer forming step, which is carried out before the narrow space undercoat layer forming step, is carried out to form the undercoat layer on the surface of the blade segment body by injecting the sprayed particles from the outside of the blade segment body. The heat shield coating method according to claim 5 , further comprising. And in the narrow space topcoat layer forming step, the wings on the basis of the shape of the body to determine in advance the narrow space, of claims 1 to 6, the spraying conditions by the first spray gun change control in accordance with the spraying position The heat shield coating method according to any one item. A wing having a plurality of wing bodies arranged in a cross-sectional wing shape and arranged apart from each other in the wing thickness direction, and a wing tip wall portion connecting the plurality of wing bodies at a base end portion in the wing height direction of the wing body. Wing to prepare the segment body The wing segment body preparation process and
The top coat layer is applied to the surface of the blade body facing the narrow space of the blade segment body prepared in the blade segment body preparation step by the heat shield coating method according to any one of claims 1 to 7. A method of manufacturing a wing segment, including a process of forming a thermal barrier coating to form a wing segment.

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