JPS58172406A - Laminated blade for gas turbine - Google Patents

Abstract

PURPOSE:To obtain a laminated blade of excellent heat resistance, corrosion resistance and strength, by alternately piling to connect plural ceramic plates formed to a sectional shape of a gas turbine blade and plural metallic plates formed to a similar shape to said ceramic plate. CONSTITUTION:Ceramic plates 1 formed to a sectional shape of a gas turbine blade and metallic plates 2 formed to a similar shape, in which a contour of the periphery is formed smaller slightly to the inside as compared with said plate 1, are alternalely piled and diffusively jointed to each other to constitute a laminated blade. Here grooves 3 forming cooling air holes are provided to the plate 1. In this way, the plate 1 distributively endures heat and corrosion further the plate 2 provides toughness and tensile strength, and excellent heat resistance, hardness, tensile strength, toughness and corrosion resistance can be obtained as a whole.

Description

[Detailed description of the invention] The present invention relates to laminated blades for gas turbines.

Since the gas turbine IR comes into contact with high-temperature combustion gas, i*
heat resistance is required. Laminated cooling blades are used for this purpose, but conventional laminated cooling blades are made by stacking thin metal plates and diffusion bonding them. The aim is to improve the cooling effect by forming a complex cooling structure.

However, in conventional turbine blades made only of metal materials, 860C to 900C is the practical limit, and anything higher than this poses problems in terms of reliability and durability. Since there is such a limit in the withstand temperature, improvement in the thermal efficiency of the gas turbine is also restricted.

i9. In the unshaped gas turbine 14 constructed using metal plates as described above, there is also a problem that corrosion occurs on the Jllj surface when inferior fuel is used.

The present invention was made in view of the above circumstances, and an object of the present invention is to provide a laminated blade for a gas turbine that has high heat resistance and reliability. Needless to say, gas turbine blades with excellent heat resistance not only directly contribute to improving the thermal efficiency of the gas turbine by making it possible to increase the gas temperature at the gas turbine inlet, but also indirectly contribute to improving the thermal efficiency of the gas turbine by making it possible to reduce the flow rate of cooling air. to 4
It can contribute to improving the thermal efficiency of gas turbines.

It has been considered to utilize materials that improve the heat resistance of gas turbines, but ceramic construction generally has more technical problems than metal materials.

The present invention exhibits the advantages of Kuryu Usec, which has excellent heat resistance, and the advantages of round metal materials, which have excellent toughness, and the disadvantages of Nanau Z ivy, which is brittle, and the disadvantages of metal materials, which have insufficient heat resistance. A large number of ceramic plates shaped like the cross-sectional shape of a gas turbine blade and a shape similar to the above (in detail, the outline of the outer periphery of the gas turbine blade It is characterized by the fact that metal plates with a cross-sectional shape similar to that of the wings (also slightly smaller in shape) are stacked on the stationery and welded together.

Iris 1wJ is an exploded perspective view showing an example of a conventional laminated stem.
It has a structure made up of a number of metal plates stacked in the cross-sectional shape of a wing.

FIG. 2 is an exploded perspective view of one embodiment of the present invention, showing a ceramic plate l formed in the cross-sectional shape of a wing, and a ceramic plate l formed in a shape with a smaller outer circumference than the Cerasec plate described above, with its outer circumference slightly moved inward. The metal plates 2 are stacked alternately, and are diffusion bonded to each other to form a laminate. In this embodiment, a plurality of ceramic plates 1 formed in the cross-sectional shape of an airfoil as described above and a plurality of metal plates 2 formed in a similar shape to this are alternately stacked and bonded to form a gas turbine. Construct a ceramic joint tool for use.

Figure 1lI3 is a perspective view of the laminate constructed as described above. In this way, by laminating the ceramic plate 1 formed in a cross-sectional shape according to the chord direction and the vertical surface and the nine metal plates 2 formed in a similar shape, a gas turbine blade with an accurate shape can be constructed with ease of joining. Easy to do.

Figure 3114 shows an embodiment different from the above. In this example, a ceramic plate formed in a cross-sectional shape with a plane substantially perpendicular to the chord direction, and a metal plate formed in a similar shape to this are used. Stack them alternately and join them.

With this configuration, the strength of the turbine blade can be increased in the blade span direction.

In order to show the details of the embodiment shown in FIG. 2, FIG. 5 is an enlarged drawing of 9 parts cut along the plane P shown in the same figure.

The outer periphery of the connecting plate 1 is formed to have the same shape as the surface of the constituent spare turbine blades, and is formed so that the outer periphery is within the thickness and the cross section T thereof is T-shaped. t is the thickness dimension of the top side of the 1-character shape.

The outer periphery of the metal plate 2 is reduced inward by the electrical dimension described above compared to the shape of the surface of the turbine blade to be constructed.

This is K, temporary l! Metal 1fL as shown by j1/s
The outer circumferential edge of No. 2 and the inner edge of the thick inside of the outer circumference of the cellar building plate are aligned in the turbine blade length direction.

FIG. 6 is a sectional view of a nine gas turbine blade constructed by laminating the ceramic plate 1 and metal plate 2 formed as shown in FIG. The top sides of the T-shaped cross sections of the outer periphery of the ceramic plate 1 mentioned above are still in contact with each other, a ceramic surface with a thickness t is formed on the surface layer of the blade of this laminate, and the outer periphery of the metal plate is directly exposed. With this configuration, the heat resistance and corrosion resistance of the gas turbine blade as a whole are significantly improved because the metal members do not come into contact with the combustion gas.

In this example, the abutment surfaces of the ceramic plate and the metal plate stacked as described above are bonded by diffusion bonding. When the present invention is actually applied, an appropriate bonding method other than diffusion bonding may be used. It is also possible to use

In this way, the gas turbine blade is constructed by alternately laminating ceramic plates and metal plates, with the ceramic member having heat resistance and corrosion resistance, and the metal member having toughness and tensile strength. Overall, it provides excellent heat resistance, hardness, tensile strength, toughness, and corrosion resistance.

In the above-described embodiment, the grooves 3 formed in the bonding surfaces of the ceramic plates 1 in a substantially perpendicular direction are round so as to constitute cooling air holes when the plates are stacked.

FIG. 7 is different from the above. A cross section of the embodiment is shown, FIG. 8 is a partially enlarged view thereof, and FIG. 519 is a perspective view thereof.

The metal 41 [2 in this example (Figs. 7 and 8) K is the metal 4 [j! It is a similar component.

This embodiment differs from the previous embodiments in that a spigot-shaped unevenness 9 is formed at the location where the T-shaped portions of the outer peripheries of two adjacent ceramic plates 1G and 1o come into contact with each other. 9 combinations, and between the outer circumferential surface of the metal plate 2 and the inner 1111 surface of the upper 2 metal plate 100 thickness! !
There are 9 things that make up 114.

As in this example, the thickness t formed on the surface of the gas turbine blade is
When combined with a ceramic layer in the form of a spigot, the metal plate 2 can be completely isolated from the combustion gas flow, and the metal plate 2 is protected by a small ceramic layer heated at 4 degrees Celsius. Since it is kept at a low temperature, it does not suffer from wear due to oxidation, and does not suffer from loss of strength due to high temperatures.

In this embodiment, in order to form a void 114, the ceramic plate 10 and the metal plate 2 are joined only at the contact surface 5, but this portion has a ceramic layer of thickness t between the combustion gas and the void. Since the temperature of the stone is low, the thermal stress caused by the difference in thermal expansion between the ceramic and the metal can be reduced, and sufficient bonding strength can be obtained.

The gap 4 formed in this embodiment communicates with the cooling air hole formed by the groove 3. The cooling air flows from the cooling 9-air header formed in the center of the wing, passes through the groove 3, and heads towards the wing surface as shown by the arrow shown in Figure 8, and the cooling air reaches the wing surface in the direction of the arrow shown in Figure 8. 114 along the inside of the blade surface in the chord direction (perpendicular to the page) and is ejected from the trailing edge into the mainstream gas. With this configuration, cooling air can be uniformly supplied to each part within the gas turbine blade.

In addition, as shown in the example of Fig. 6, only the cooling holes extending from the cooling 9 air header in the center of the turbine blade to the blade surface are
If formed by #13, cooling can be performed with a simple configuration, and the cooling airflow flowing towards the blade surface in #13 is directed to the blade surface KtIA and performs film cooling, so that the gas turbine blade conducts from the combustion gas. The amount of heat generated can be reduced.

Since the gas turbine blade to which the present invention is applied has no metal members exposed on the surface, there is no risk of corrosion on the blade surface even when using inferior fuel. , even if a part of the ceramic plate is damaged due to a crack like that shown in 6, there is no risk of damage to the metal plate 2 because it does not come into direct contact with the combustion gas. Even if a part of the lamic board is damaged due to cracks like
Cooling air is ejected from this defect into the mainstream gas, and the outer peripheral surface of the metal plate 2 is surrounded by the cooling air flow, so there is no risk of serious damage.

Also, even if a crack occurs and grows in the K14 chord direction on the blade surface, the crack stops growing at the boundary with the adjacent ceramic plate, so the crack is wide! There is no risk that it will reach 8.

As explained above, one aspect of the present invention is to alternately stack and bond a plurality of ceramic plates formed in the cross-sectional shape of a gas turbine blade and a plurality of metal plates formed in a similar shape to the above. Furthermore, a laminated gas turbine blade with high heat resistance and reliability can be constructed.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view of a laminated type gas turbine blade commonly used in the past, Fig. WJ2 is an exploded perspective view of an embodiment of the ceramic bonded 1j11-blade for gas turbines according to the present invention, and Fig. 3 is FIG. 4 is a perspective view of an embodiment different from the above, FIG. 5 is an exploded perspective view taken along the P plane of the ninth embodiment shown in FIG. 2, and FIG. 6 is a cross-sectional view showing the assembled state. , FIG. 7 is a sectional view of another embodiment in an assembled state, FIG. 8 is an enlarged sectional view, and FIG. 9 is a perspective view. 1...Ceramic plate, 2...Metal plate, 3...Groove forming the cooling air hole, 4...Group forming the cooling air hole, 5...Joint surface, 6.7...・Imaginary crack, 10
... Sera ζ Tsuku board.

Claims (1)

[Scope of Claims] 1. It is characterized by a layer in which a plurality of ceramic plates formed in the cross-sectional shape of a gas turbine blade and a plurality of metal plates formed in a similar shape to the above are alternately stacked and bonded. laminated blades for gas turbines. 2. The laminated blade for a gas turbine according to claim 1, wherein the cross-sectional shape of the gas turbine blade is a cross-sectional shape formed by a plane perpendicular to the blade span direction. 3. The cross-sectional shape of the gas turbine blade is characterized by being a cross-sectional shape of a plane substantially perpendicular to the chord direction of the blade.
A laminated blade for a gas turbine y according to item 1 of the request for Fl11. 4. The ceramic plate is formed into a thick inner shape along the outer peripheral edge, and the outer peripheral shape of the metal plate is shrunk inward by a certain dimension from the contour of the cross section of the blade, and the ceramic plate is Claims characterized in that the outer circumferential surface of a laminate formed by stacking plates and metal plates alternately is formed of ceramic, and the outer circumferential surface of the metal plates is configured so as not to be exposed on the surface of the laminate. A laminated wall for a gas turbine according to item 1, item 2, or item 3. 5. Claim 1, characterized in that a joint surface K11I is formed between the ceramic plate and the metal plate, and cooling air holes are formed inside the laminate made by stacking these plates alternately. , Paragraph 2 of the same, Paragraph 3 of the same, or Paragraph Is4 of the same Kit
Laminated blades for e-mounted gas turbines. 6. The laminated layer for a gas turbine according to claim 6, characterized in that the cooling air holes are directed from the cooling air header at the center of the turbine toward the blade surface. Wings. 7. The cooling air holes are directed from the cooling air header at the center of the turbine toward the blade surface WJ, and along the inside of the true surface in the chord direction, communicating with the mainstream gas at the trailing edge. Claim 5 is characterized in that:
A laminated blade for a gas turbine as described in 2.