JPS5817323B2 - Gaster Binyoku - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to gas turbine blades, and in particular to porous materials,
For example, the present invention relates to a gas turbine blade that improves cooling efficiency by using blades that are made of powdered sintered metal and have a highly thermally conductive aggregate incorporated therein.

Generally, in gas turbines, it is required to increase the temperature of the mainstream gas in order to improve the thermal efficiency of the turbine.

On the other hand, blades whose surfaces come into direct contact with high-temperature mainstream gas have a limited heat resistance due to the nature of the material.

For this reason, efforts are being made to cool the blades to increase the balance between blade strength and mainstream gas temperature.

In particular, during cooling, if the blade is cooled uniformly, the temperature distribution on the surface of the blade will be uneven, resulting in the highest temperature and lowest temperature areas, which will generate extra thermal stress and further increase the temperature of the highest temperature area. The disadvantage is that the strength of the blades is reduced.

In conventional blades, when using ordinary super heat-resistant alloy materials, countermeasures to this drawback were taken by changing the size and arrangement of the cooling holes, but this caused many problems in terms of processing accuracy.

Recently, attempts have been made to obtain a good cooling effect for blades using porous materials by adjusting the arrangement and cross-sectional area of the refrigerant flow path surrounded by the partition plate using a core body and partition plate. There is.

However, in this case as well, the manufacturing method is difficult and the number of partition plates is limited, so that sufficient effects cannot be achieved.

Theoretically, it is clear that in order to make the temperature distribution uniform on the blade surface, a material with good thermal conductivity should be used for the blade material.

However, materials with good fuel conductivity have the disadvantage of low strength, especially at high temperatures.

This invention was made to eliminate the above-mentioned drawbacks, and is formed by using porous materials such as powdered sintered metal and wire cloth, and incorporating aggregates with good thermal conductivity inside. The objective is to provide a gas turbine blade with high strength and a substantially uniform temperature distribution on the blade surface.

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

Figure 1 shows porous material 1 obtained by the manufacturing method described below.
It is a blade 3 of a rotor blade formed by incorporating aggregate 2 with good thermal conductivity inside.

As shown in FIG. 2, the core body 5 inserted into the hollow part 4 of the blade 3 is fixed at its base to the mounting seat 6.

This mounting seat 6 has a refrigerant supply hole 8 bored inside.

On the other hand, cooling holes 10 are bored inside the core body 5 along the direction of the centrifugal force generated by the rotation of the rotor blades, and communicate with the coolant supply holes 8 .

Furthermore, from the side of the cooling hole 10, there is a refrigerant blowout hole 1 in a right angle direction.
A large number of holes 2 are formed, and the other end is opened on the surface of the core body 50.

Therefore, the refrigerant introduced from the supply hole 8 passes through the cooling hole 10, is blown out from the blow-off hole 12 onto the surface of the core body 5, and soaks into the inside of the fitted blade 3 as shown by the chain line in FIG. .

Further, a cap 14 as shown in FIG. 3 is fitted to the tip of the core body 5 so that its lower surface is joined to the top surface of the tip of the blade 3.

The lid body 16 is fitted and fixed into the top surface of the tip of the core body 5 so as to close the opening at the tip of the cooling hole 10 .

This situation is shown in FIGS. 2 to 4 together with dashed lines.

In addition, as shown by the chain line in FIG. 2, the blade 3 is connected to the core body 5.
The cap 14 is supported by the hollow portion 4, and both end surfaces are tightly pressed and held by the top surface of the mounting seat 6 and the bottom surface of the cap 14.

When the turbine in the rotor blade configured in this manner is put into operation, a refrigerant, for example, cooling water, is fed from the supply hole 8 to the blowout hole 12 through the cooling hole 10 .

The cooling water penetrates into the blade 3 from here and cools the entire blade from the inside.

It goes without saying that a portion of this cooling liquid also cools the core body 5 and the cap 14 at the same time.

Further, due to the presence of the material 2 having good thermal conductivity, the temperature distribution within the blade 3 is made uniform, and there is almost no risk of the blade becoming locally heated or generating excessive thermal stress.

Next, one example of a method for manufacturing the above-mentioned blade 3 will be described in detail.

After forming and forming the aggregate 2 by arranging wire mesh made of copper wire (diameter Jφ) in a geometric grid pattern as shown in Fig. 1,
After heating at 900°C for 3 hours in high-purity N2 gas and solid-phase bonding at the mutual contact parts of the aggregates 2, the Ni-50 with a thin film of maximum 0.2μ was placed in a vacuum evaporator.
%Cr alloy is deposited uniformly on its surface.

Next, the aggregate 2 of the copper wire mesh is charged into the blade forming mold,
Furthermore, the voids are filled with 1325 mesh Inconel alloy powder to the extent that the lattice arrangement of the aggregate 2 is not extremely deformed, and the powder is compacted at 60 t/ant to obtain a compact in the shape of the desired blades 3. get.

After sintering this compact in a high-temperature vacuum sintering furnace at 1050°C for 5 hours, the sintered compact was vacuum sealed in a stainless steel pack, and then charged again into the isostatic press molding machine using Ar gas pressurization. Then, the final blade 3 is obtained by performing a densification treatment at a temperature of 1000° C. for 1 hour under conditions of 1200 atm.

Although the above-mentioned embodiment describes a case where this blade is applied to a rotor blade, this is not intended to limit the scope of the present invention.

That is, even if it is used as a vane of a stationary blade, the same effect can be achieved in making the temperature distribution uniform.

However, to supply refrigerant, centrifugal force is not used as in the case of rotor blades, so an external device such as a pump should be used, the blades may be solid, and a core body and cap are not always required. Of course not.

Further, although the blades in the above-described embodiments are made of powdered sintered metal, they can also be formed by wire cloth.

The cross-sectional structure of the wire cross in this case is shown in FIG.

In the figure, the dotted diagonal line is a wire 18 made of a good heat conductive material, and the blade 3 is formed from a wire cloth made by twisting this wire 18 and a wire 20 made of a heat-resistant metal.

These twisted wires are arranged so as to intersect with each other in the longitudinal and lateral directions of the blade, thereby improving heat conductivity in both the longitudinal and lateral directions, and providing sufficient strength due to the heat-resistant metal wires 20.

In this example, a porous material with a certain degree of flexibility is obtained, so the blades can be easily formed, and since the heat-resistant metal and the material with good thermal conductivity are made separately, the joints can be easily formed. It has the advantage of not peeling off.

In addition, Fig. 5 shows an example in which the vertical and horizontal twists are woven at the same spacing, but it is possible to place them mainly near the leading edge and trailing edge where the temperature is high, or to make the weft yarns denser and the warp yarns sparser. Cooling efficiency will further improve.

As is clear from the above, according to the present invention, a blade is formed by forming a blade from a porous material such as powdered sintered metal and wire cloth, and incorporating an aggregate with good thermal conductivity into the material. Since gas turbine blades using this method can be obtained, they are strong, have a uniform temperature distribution on the blade surface, and can achieve efficient seepage cooling, which has many practical effects.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of a blade according to the present invention, FIG. 2 is a perspective view showing a core body of the same embodiment as FIG. 1,
FIG. 3 is a perspective view showing the same embodiment of the cap as in FIG. 1;
Fig. 4 is a perspective view showing the lid body of the same embodiment as Fig. 1;
The figure is a partial cross-sectional view showing another embodiment of the blade according to the present invention. 1... Porous material, 2... Aggregate with good thermal conductivity, 3.
...Blade, 4...Hollow part, 5... Core body, 6...
Mounting seat, 8... Refrigerant supply hole, 10... Cooling hole, 14
...Cap, 18...Good thermal conductive wire, 20...
・Heat-resistant metal wire.

Claims (1)

[Claims] 1. A hollow blade formed by incorporating a highly thermally conductive aggregate into a porous heat-resistant material, a core body having cooling holes inserted into the hollow part of this blade, and the blade are fixed to each other. A gas turbine blade comprising a mounting seat and a refrigerant supply hole that communicates with a cooling hole of the core body bored inside the mounting seat.