JPH05209536A - Gas turbine - Google Patents

Abstract

PURPOSE:To reduce stress working on a turbine blade and simplify a sealing plate by positioning a sealing plate in the circumferential direction of the turbine blade, mounting the plate on a positioning member in a contilevered way, and by pressing the sealing plate to the under surface of a platform which is in close proximity to the plate. CONSTITUTION:Turbine blades 7-9 are inserted into a plurality of mounting grooves 14 formed on the outer peripheries of rotor discs 10-12. A positioning member 25 opposed in the axial direction of the turbine blades 7-9 is mounted on the rotor discs 10-12. The turbine blades 7-9 have platforms 22 between a blade main body 20 and a mounting part 21. Sealing plates 30 positioned in the circumferential direction of the turbine blades 7-9 are mounted on the positioning member 25 in a contilevered way. The sealing plate 30 is pressed to the under surface of the platform 22 which is in the close proximity with the plate by centrifugal force, so that circumferential gaps formed between the platforms 22 which are in the close proximities to one another can be sealed.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to gas turbines having implantable turbine blades.

[0002]

2. Description of the Related Art FIG. 7 shows an implantable turbine blade 1
01, which comprises a blade body 102, an implant 103, and a platform 104 between the blade body 102 and the implant 103.
The implanting portions 103 are axially inserted into implanting grooves formed at intervals in the circumferential direction on the outer circumference of the rotor disk. The turbine blade 101 inserted in the implantation groove is axially positioned by a positioning member attached to the rotor disk.

In the gas turbine having the implantable turbine blade 101 as described above, a gap δ is provided between the adjacent platforms 104 in the circumferential direction to prevent interference due to thermal expansion. Such a gap δ
When a part of the combustion gas flows from the
The temperature of the implanting part 103 rises, and conversely, the gap δ
Is injected into the combustion gas passage 106 from the above to cause a trouble such as disturbing the main flow of the combustion gas passage.

Therefore, the adjacent platforms 10
4, a container-like seal member 10 as shown in FIG.
5 was inserted and the seal member 105 was pressed against the lower surfaces of both platforms 104 by centrifugal force to seal the gap δ.

[0005]

In the above conventional structure,
Since all the centrifugal force acting on the seal member 105 acts on the turbine blade 101, there is a problem that the stress acting on the turbine blade becomes large.

Further, since the seal member 105 needs to be formed of a sheet metal material into a container shape and further needs to be formed so as to match the space shape between adjacent turbine blades, a high manufacturing technique is required. However, the manufacturing cost was high.

Further, there is a problem that the sealing member 105 itself loses its shape due to the centrifugal force, and the sealing function cannot be achieved.

It is an object of the present invention to provide a gas turbine that can solve the above-mentioned problems of the prior art.

[0009]

A feature of the present invention is that a plurality of grooving grooves are formed in the outer circumference of a rotor disk at intervals in the circumferential direction, and a turbine blade is axially provided in each grooving groove. A positioning member for axial position of the turbine blade inserted in the implantation groove is attached to the rotor disk, and each turbine blade is provided between the blade body and the implantation portion inserted in the implantation groove. In a gas turbine having a platform, the positioning member is cantilevered with a seal plate located between the turbine blades in the circumferential direction, and each seal plate seals a gap between the adjacent platforms in the circumferential direction. Centrifugal force forces it against the underside of adjacent platforms Located in.

[0010]

According to the structure of the present invention, since the seal plate is attached to the positioning plate in a cantilever manner, all of the centrifugal force acting on the seal plate does not act on the turbine blade but on the turbine blade. Stress is reduced.

The seal plate need only have a simple shape so that it can contact the lower surfaces of the adjacent platforms, so that it is easy to manufacture and does not lose its shape even when centrifugal force is applied.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

The gas turbine 1 shown in FIG.
And an output turbine 3 and a compressor 4. The combustor 2 is connected to a scroll chamber 5, a combustion gas passage 6 is connected to the scroll chamber 5, and compressor turbine blades 7 and 8 and an output turbine blade 9 are arranged in the combustion gas passage 6. The compressor turbine blades 7 and 8 are the compressor 4
Are mounted on the outer circumferences of the drive rotor disks 10 and 11, and their output turbine blades 9 are mounted on the outer circumference of the rotor disk 12 of the output turbine 3.

As shown in FIGS. 4 and 5, a plurality of blade-implanting grooves 14 are formed on the outer circumference of each of the rotor disks 10, 11 and 12 at intervals in the circumferential direction. Each implant groove 14 includes a rotor disk 10, 11,
It is formed so as to have a twist angle with respect to the axial direction of 12, and a wide portion 14a is formed inward in the radial direction. Each implantation groove 1
Turbine blades 7, 8 and 9 are axially inserted into the shaft 4.

As shown in FIG. 1, each of the turbine blades 7, 8 and 9 includes a blade body 20, an implant portion 21,
It has a platform 22 between the blade body 20 and the implanting portion 21, and the radially inner end of the implanting portion 21 is a wide portion 21a. As a result, the implanting portion 21 is inserted into the implanting groove 14, and as shown in FIGS. 2 and 3, the wide portion 2 of the implanting portion 21 is inserted.
1a contacts the inner surface of the wide portion 14a of the implantation groove 14,
The turbine blades 7, 8, 9 are prevented from coming off in the radial direction.

The turbine blades 7, 8 and 9 inserted in the grooving grooves 14 have rotor disks 10, 11 and 12 respectively.
In order to prevent the rotor discs 10, 11 and 12 from axially slipping out, positioning members 25 and 26 at the axial positions of the turbine blades 7, 8 and 9 are attached to both surfaces thereof. Each positioning member 25, 26 is a ring-shaped plate, and as shown in FIG.
11 and 12 and the headed pin 27 inserted into both positioning members 25 and 26 are fixed by being caulked.

As shown in FIGS. 1 and 2, a seal plate 30 positioned between the turbine blades 7, 8 and 9 in the circumferential direction is cantilevered on one of the positioning members 25. The seal plate 30 is L-shaped in a side view in this embodiment, and is fixed to the positioning member 25 by spot welding. Each seal plate 30 is pressed against the lower surface 22a of the adjacent platform 22 by the centrifugal force, and the gap δ between the adjacent platforms 22 is increased.
Seal.

As a result, the rotor disk 1 is moved from the gap δ between the platforms 22 where some of the combustion gases are adjacent to each other.
It is possible to prevent the cooling air from flowing into the 0, 11, 12 side, or conversely, from flowing out or jetting from the gap δ into the combustion gas passage. A part of the centrifugal force acting on the seal plate 30 is part of the rotor discs 10, 11, 12
Since it is supported by, the stress acting on the turbine blades 7, 8, 9 does not become excessive, and damage to the turbine blades 7, 8, 9 can be prevented. Further, the seal plate 30 has a simple shape and is easy to manufacture, so that the cost is low,
Since the shape does not collapse due to centrifugal force, the sealing function can be surely achieved.

Further, in this embodiment, as shown in FIGS. 3 to 5, the outer peripheral surface 10 of the rotor disks 10, 11 and 12 is used.
extension part 3 extending outward in the radial direction from a, 11a, 12a
5 is provided integrally with the rotor discs 10, 11, 12 and the extension 35 of each is provided with the respective turbine blades 7, 8, 9
It is close to the lower surface 22a of the platform 22 of. This prevents the combustion gas from flowing in the axial direction through the lower surface 22a of each platform and the outer peripheral surfaces 10a, 11a, 12a of the rotor disks, and prevents the turbine output from decreasing. In addition, each extending portion 35 is provided with a recess 35 a for disposing the seal plate 30.

The present invention is not limited to the above embodiment. For example, although the present invention is applied to both the compressor turbine blade and the output turbine blade in the above embodiment, it may be applied to only one of them. Further, the shape of the seal plate and the method of attaching it to the positioning member are not limited to those in the above embodiment.

[0021]

According to the gas turbine of the present invention, the seal plate that seals the circumferential gap between the platforms of the implantable turbine blades has a simple shape that can be easily manufactured. Since it does not collapse, it is possible to reliably perform a sealing function, prevent a decrease in turbine output, and reduce the manufacturing cost. Further, since the stress acting on the turbine blade is reduced, it is possible to prevent the turbine blade from being damaged.

[Brief description of drawings]

FIG. 1 is a perspective view of a turbine blade and a seal plate according to an embodiment of the present invention.

FIG. 2 is a side sectional view of a turbine blade according to an embodiment of the present invention.

FIG. 3 is a front sectional view of a turbine blade according to an embodiment of the present invention.

FIG. 4 is a perspective view of a rotor disk according to an embodiment of the present invention.

FIG. 5 is a front view of a rotor disk according to an embodiment of the present invention.

FIG. 6 is a sectional view of a gas turbine according to an embodiment of the present invention.

FIG. 7 is a perspective view of a conventional turbine blade and a seal member.

[Explanation of symbols]

 7, 8 and 9 Turbine blades 10, 11 and 12 Rotor disk 14 Implanting groove 20 Blade body 21 Implanting part 22 Platform 25 Positioning member 30 Seal plate

Claims (1)

[Claims] 1. A plurality of embedding grooves are formed on the outer circumference of a rotor disk at intervals in the circumferential direction, and a turbine blade is inserted into each of the embedding grooves from the axial direction along the groove direction and is inserted into the embedding grooves. A turbine blade axial position locating member is attached to the rotor disk, each turbine blade, in the gas turbine having a platform between the blade body and the implant portion inserted into the implant groove, in the locator member, The seal plates located between the circumferential directions of the turbine blades are attached in a cantilever manner, and the respective seal plates can centrifugally force the adjacent platforms so as to seal the gap between the circumferential directions of the adjacent platforms. A gas turbine characterized by being pressed against the lower surface of the gas turbine.