JPS59203809A - Mounting structure of moving vane for axial-flow type turbo-machine - Google Patents

Abstract

PURPOSE:To prevent the generation of a backlash between a moving vane and a disk by holding heat-resisting heat-insulating pads among the indentations of the disk divided into two by a surface vertical to a shaft and a moving vane mounting section connected to the indentations. CONSTITUTION:Heat-resisting heat-insulating pads 3, 5 are held among the indentations 28 of disks 25 divided into two by surfaces vertical to a shaft 24 and the mounting sections 2 of moving vanes 26 connected and mounted to the indentations 28. Differences among thermal expansions of the moving vanes 26 and the disks 25 can be absorbed by the pads 3, 5. Accordingly, the generation of backlashes among the moving vanes 26 and the disks 25 can be prevented even when a turbo-machine is operated under high centrifugal force at a high temperature.

Description

[Detailed description of the invention] Unexploded 8J written axial flow type turbo blower, turbo compression (('
In addition, &1 turbo original "t11", that is, axial flow type turbo m
The present invention relates to a structure for attaching a ceramic rotor blade to a disk at t'+=.

Recently, efforts have been made to increase the thermal efficiency and save energy by increasing the temperature of the PD+ gas in the production of axial flow turbo machines.

However, with the metal rotor blades currently in use, the angle is approximately 900°.
Since the corrosion resistance, abrasion resistance, and strength at high temperatures that produce C are insufficient, it is impossible to circulate or pump high-temperature gas or to efficiently extract power from high-temperature scum, especially those containing dust. The thermal energy of corrosive Takatoro 1 gas cannot be used effectively. In other words, the conventional "metal-perforated" moving blades have already reached their technical limits, and unless there is a radical technological innovation, it is difficult to change the current situation.

Ceramic is currently the only material for rotor blades that can withstand the corrosive gas, and research on ceramic blades is being carried out in various fields.

The following methods are conventionally known for attaching metal rotor blades to axial flow tarpole rods.

One of them is the gold vi of turbomachinery: several parts of the rotor blades are provided parallel to the disk axis with a dovetail-shaped or Christmas tree-shaped recess on the circumference of the disk, and have mounting portions that fit snugly into the recess. , it is installed by inserting it parallel to the disk axis from the circumference of the disk side. The other method is to provide a concave portion with a convex cross-section on the peripheral edge of the disk.
Several parts of the rotor blade, each of which has several parts that fit snugly into this convex recess, are sequentially inserted into the insertion opening provided by cutting out a part of the peripheral edge, and are slid in the circumferential direction to remove the rotor blade. is placed and installed in a predetermined position.

However, even if these methods are applied to ceramic rotor blades, due to the large difference in thermal expansion coefficient between ceramic and metal, play will occur between the disk and the rotor blade under high temperature and high centrifugal force. The use of ceramic rotor blades is impossible because the rotor blades and the rotor blade mounting portion of the metal disk collide violently, resulting in damage to the rotor blades 1' and/or the disks.

The object of the present invention is to attach a ceramic rotor blade to a metal disk so that it can be maintained without rattling between the blade and the disk even when operated under high centrifugal force against high-temperature gas exceeding 900'C. Do not run out of power or damage the disc (
・Providing axial flow type turbomachinery.

The rotor blade mounting structure for an axial flow turbomachine according to the present invention has a recess that is widened from the periphery toward the axis, and is divided into two parts on a plane perpendicular to the rotating shaft, and can be fastened with a fastener. The mounting portion of a ceramic rotor blade consisting of a wing portion and a sliding mounting portion that engages in the recess is accommodated in the recess of the disk, and a heat-resistant insulation [+- pad] is provided between the mounting portion and the recessed surface. holding the
It is characterized in that the split disks are fastened together using the fastener.

In a preferred embodiment of the rotor blade mounting structure according to the present invention,
The pad is sandwiched between the shoulders of the sections and the recessed surface, and between the bottoms of the sections and the recessed surface.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The rotor blade structure of the axial flow type turbo spar according to the present invention will be explained below based on the drawings of the embodiments.

In FIG. 1, a single stage or multiple stages (two stages in FIG. 1) of discs 25 are attached to a rotating shaft 24 which is received by a bearing 23. A plurality of ceramic movable grooves 26 are attached radially around the periphery of each nice 2250. A stator blade 22 is fixed to the casing 20 outside the rotor blade 26 and protrudes inward. A shroud 21 and a casing 2 made of suitable heat insulating material are provided to handle the disk 25.
The working gas flows in the space of 0 ml as shown by the arrow.

The disk 25 is provided with a recess 28 which is tapered from the periphery toward the axis (the tapered portion is indicated by reference numeral 27) and widened.Therefore, a recessed surface is formed inward from the peripheral surface of the disk 25. In addition, the disk 25 is divided into two divided disks 6.7 having a substantially bilaterally symmetrical shape in a plane perpendicular to the rotational axis 24.The divided disks 6.7 are connected to a suitable fastener, such as a pol) 9.11. and Natsu 10.12
They are mutually concluded and tightly linked. Further, cooling holes 17 communicating with the recesses 28 from the outer surface of the disk are provided in the divided disks 6.7, and holes 18 are also provided as communication holes between the divided disks 6.7, depending on the necessity of air intake. ing.

The ceramic rotor blade 26 consists of a part 2 and several parts 2.

The attachment portion 2 has a shape that engages with the recess 28, that is, the attachment portion 2 is wider on the side accommodated in the disk 25 than the side that connects with the wing portion, and a tapered portion is provided in the middle thereof. and forms a shoulder portion 29. Tapered portion 27 of concave surface of disk 25 and peripheral portion 2 of blade 1)
Pad 3 and Pad 5 are sandwiched between the bottom of the surface and the bottom of the attachment part of the rotor blade, respectively, and the bottom of the pad 5 A spring 30 is placed between the bottom of the recess and the bottom of the recess.
In order to prevent the position of the spring 30 from shifting, a recess is formed in the spring abutting section at the bottom of the concave surface, but it may also be omitted. Further, a recess P9i may be formed in the taper portion 27 that the punt 3 hits.

Pads 3 and 5 have heat resistance and heat insulation properties, and are preferably made of metal and/or ceramic. Because this turbomachinery is mainly used under high-temperature gas flow, and because it is desired to suppress heat conduction from the ceramic rotor blades to the metal disk, the pad is heat-resistant and insulating. It is desirable to have a suitable amount of elasticity because it is desired to absorb backlash and vibration.

As an example of the bands 3 and 5, these pads are made of heat-resistant metal such as nickel, stainless steel, Inconel, and Hastelloy, and preferably, as shown in FIG. A plurality of parallel holes 4 are bored in the pad 3 through which cooling air can flow from the pad 3 to the wing side. These holes allow the pad 3 to have a sufficient temperature gradient and to exhibit elasticity. Further, the pad 5 may have the same shape as the pad 3 shown in FIG. 2, or it may have an H-shaped cross section as shown in FIG. 2 to reduce heat conduction from the bottom of several parts to the disk. You can do it like that.

The pad is made by forming thin wires of heat-resistant metal into a wire mesh shape and sintering it (so-called sintered wire mesh).

Pads 3 and 50 In further embodiments, these pads contain ceramic powders or ceramic solids based on magnesia, alumina, zirconia, silica, silicon nitride, etc. within a heat-resistant metal shell. .

The pads of any of these embodiments have surface heat resistance, thermal insulation properties, and moderate elasticity.

To attach the rotor blades 26 to the disk 25, arrange the attachment parts 2 of the plurality of rotor blades 26, sandwich the pad 3 between the tapered part 27 and the shoulder part 29, and insert it into the recess of one of the divided discs 6. Then, i between the bottom of the several parts 2 and the bottom of the concave surface 1 is
Insert the pad 5 and spring 30 into the hole. Next, PJi
? When the pad 3 of the pad 3 is held between the pads 3 and the other split disc 7 is placed over the split disc 6.7 and the split discs 6 and 7 are tightened with bolts and nuts, the mounting part 2 is pressed toward the axis by the action of the 7 to 7 parts 27. , the rotor blade 26 is fixed to the disk 25 at a position that balances the drag force of the spring 30.

In Fig. 1, bolts, nuts, etc. are fastened at two different radii from the axis, but they can be increased or decreased as appropriate, and they can also be tightened in the circumferential direction at each rotor blade. It doesn't have to be the same number;
You may thin it out as needed. It is also preferable that the bolts 9 in FIG. 1 pass through several parts 2 of the rotor blade, and as shown in FIG. It is desirable to pass the bolt evenly.

In this tarpol machine, the rotor blade 26 is connected to the disk 25.
Since the rotor blades 26 are insulated by the heat insulating pad 3, even if the temperature of the rotor blades 26 is high due to high-temperature gas, the disk 2
The amount of heat transferred to the disk 5 is small, and the temperature rise of the disk 25 is suppressed. In particular, when cooling air is supplied through the cooling air holes 17 and, if necessary, the circulation air holes] 8 within two days of the depression, the temperature rise of the disk 25 can be further suppressed. Therefore, a decrease in strength and corrosion resistance due to the rise of the disk 25 due to mud can be prevented. Although the pad 3 is in contact with the high-temperature rotor blade 26, it will not deteriorate if it has sufficient heat resistance, and there will be no problem, especially when it is cooled with cooling air. Although the rise of the disc 25 is suppressed, it is often unavoidable that the width and thickness of a certain culm increase, and the difference in expansion between the ceramic rotor blade 26 and the disc 25 due to this temperature rise is due to the elasticity of the spring 300. Also, the rotor blades 26 are not loosened.

The rotor blade attachment part of the ceramic blade of the Kinryu-type turbo machine according to the present invention is coated as described above, and its constituent members function as described above, so that the ceramic rotor blade is firmly held on the disk. '11. The temperature rise of the disc is also suppressed, and even when driving the Terhosshi' Hayashi under high g1 centrifugal force, the moving plate is fixed with two pads in the concave part of the disc, and no warping occurs. , there is a risk of breaking the parts.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a half of the road in a plane including the rotating shaft of the rotor blade mounting structure of a cast turbine according to an embodiment of the present invention, and FIG. 2 shows the arrangement of the rotor blade 1, bolts 9, etc. in FIG. 1. FIG. DESCRIPTION OF SYMBOLS 1... Wing part, 2... Mounting part, 3, 5... Nokurado, 6.7... Divided disk, 28... Recess. Chapter J Obesity? sword

Claims (2)

[Claims] (1) The wing portion engages with the concave portion of the disk, which has a concave width that is narrowly widened from the periphery, is divided into two parts on a plane perpendicular to the rotation axis, and can be fastened with a fastener. At the same time, a heat-resistant and heat-insulating band is sandwiched between the mounting part and the recessed surface, and the split discs are fastened together with the fastener. A rotor blade mounting structure for axial flow type turbo sweeping. (2) The rotor blade mounting structure according to claim (1), wherein the pad is sandwiched between the shoulder of the mounting portion and the recessed surface, and between the bottom of the mounting portion and the recessed surface.