JP2015151891A - gas turbine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas turbine capable of preventing failures caused by foreign objects mixed in the gas turbine from outside or those produced by rust or the like.SOLUTION: Provided is a gas turbine 1 in which compressed air at a predetermined temperature moves in an internal channel when the gas turbine 1 is active, and in which a substance 6 that is softened at an atmospheric temperature and softened at the temperature of the compressed air passing through part of a surface forming the channel is coated on at least the part of the surface forming the channel. The substance 6 can thereby adsorb and hold foreign objects.

Description

  The present invention relates to a gas turbine.

Since the working fluid is air, a gas turbine mainly uses an open system, and is required to be robust against contamination from outside.
On the other hand, in recent gas turbines, a precise and fine flow path is designed for cooling and the like, and a small amount of mixed foreign matter is clogged, and it is beginning to have many adverse effects.

  In particular, since the metal is exposed to a situation where oxygen is present at a high temperature, rusting due to oxidation and mixing of rust into the gas turbine due to separation of these rusts cannot be avoided. And, due to rust contamination in the gas turbine, the gas turbine cooling efficiency decreases, abnormal wear due to rust collisions on the blade surface, damage from vibration due to vibration eigennumber change due to rust adhesion on moving parts, etc. Various types of damage are induced.

  As a technique for eliminating the influence of rust, a foreign matter removing structure as described in Patent Document 1 is known. This structure is a structure provided with a collection port through which foreign matter enters the turbine shroud constituting the gas turbine and leads out of the flow path.

JP 2002-242695 A

  However, the foreign matter removing structure described in Patent Document 1 has a problem that a large introduction cost is required because a new structure needs to be added to the gas turbine.

  An object of the present invention is to prevent problems caused by foreign matters mixed in from the outside or foreign matters generated by rust or the like in a gas turbine.

  According to the first aspect of the present invention, the gas turbine is a gas turbine in which compressed air having a predetermined temperature moves in an internal flow path during operation, and at least a part of a surface forming the flow path has an atmosphere. A substance that is in a cured state at a temperature and is in a softened state at a temperature of compressed air that passes through the part during operation of the gas turbine is applied.

According to such a configuration, even when foreign matter is mixed in the flow path of the gas turbine, the foreign matter can be adsorbed and held by the softened substance. Thereby, the malfunction which a foreign material causes can be prevented.
Moreover, compared with filtration apparatuses, such as a filter, a foreign material can be collected, without producing pressure loss.
Moreover, since there is no need for an installation place, it can be introduced into an existing plant at low cost.
Further, since the substance is in a cured state at the atmospheric temperature, the operation can be performed without causing any trouble during the maintenance operation of the gas turbine. Moreover, since it will be easy to peel a substance if it is a hardening state, the work efficiency of a maintenance work can be improved.

  In the gas turbine, the substance may be a covalent bond substance that is softened by glass transition at an operating temperature of the gas turbine.

  According to such a configuration, the substance does not become a liquid phase by heating from the solid phase, but becomes a glass phase (soft solid phase), and thus can be softened while maintaining the shape coated with the substance.

In the gas turbine, the substance may be a low melting point glass.
According to such a configuration, since the softening point of the low-melting glass is about 450 ° C., a material suitable for a surface exposed to high-temperature compressed air can be obtained.

In the gas turbine, the substance may be an organic polymer compound.
According to such a configuration, it is possible to obtain a material suitable for the surface exposed to the cooled compressed air by adopting an organic polymer compound equivalent to the compressed air whose softening point is cooled.

  The gas turbine may include a cooling system that cools at least a part of the turbine, and the substance applied to the flow path through which the compressed air cooled by the cooling system flows is an organic polymer compound. Good.

  ADVANTAGE OF THE INVENTION According to this invention, the malfunction caused by the foreign material mixed from the outside or the foreign material produced | generated by rust etc. can be prevented in a gas turbine.

It is a schematic block diagram of the gas turbine of embodiment of this invention.

Hereinafter, a gas turbine 1 according to an embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic view of a gas turbine 1 according to an embodiment of the present invention. As shown in FIG. 1, a gas turbine 1 includes a compressor 2 that compresses outside air to generate compressed air A, a combustor 3 that burns fuel in the compressed air A to generate combustion gas G, and a high temperature A turbine 4 driven by high-pressure combustion gas G, and a cooling system 5 that cools a high-temperature portion in contact with the combustion gas G in the gas turbine 1 are provided. During operation of the gas turbine 1, the compressed air A having a predetermined temperature moves through the internal flow path.

  The compressor 2 includes a compressor rotor 7 and a compressor casing 8 that covers the compressor rotor 7. The compressor rotor 7 includes a compressor rotor shaft portion 9 that rotates about a rotation center axis, and a plurality of compressor blades 10 that are fixed to the outer periphery of the compressor rotor shaft portion 9. A plurality of compressor vanes 11 are fixed to the inner peripheral side of the compressor casing 8.

The turbine 4 includes a turbine rotor 13 and a turbine casing 14 that covers the turbine rotor 13. The turbine rotor 13 includes a turbine rotor shaft portion 15 that rotates about a rotation center shaft, and a plurality of turbine blades 16 that are fixed to the outer periphery of the turbine rotor shaft portion 15. A plurality of turbine vanes 17 are fixed on the inner peripheral side of the turbine casing 14.
A cooling air flow path 19 through which cooling air for cooling the turbine rotor blade 16 passes is formed in the turbine rotor shaft portion 15 and the turbine rotor blade 16.
For example, a generator 20 that generates electric power by rotation of the turbine rotor 13 is connected to the turbine rotor 13.

The compressor rotor 7 and the turbine rotor 13 are integrally connected by an intermediate shaft 21. A ring-shaped intermediate shaft cover 22 is attached to the outer periphery of the intermediate shaft 21.
The combustor 3 has a combustor casing 24, and a combustor casing 25 is formed inside the combustor casing 24.

  The cooling system 5 includes an extraction line 26 that extracts compressed air A from the compressor 2, a cooling device 27 that cools the compressed air A that has passed through the extraction line 26, a filter 28, and a compression that is cooled by the cooling device 27. A cooling air line 29 for guiding the air A to the cooling air flow path 19.

Since the gas turbine 1 has the above configuration, the gas turbine 1 has a flow path through which the compressed air A flows. That is, the compressed air A generated by the compressor 2 is introduced into the combustor 3 or the like via the flow path. At this time, the inner surface of the combustor casing 25 and the outer peripheral surface of the intermediate shaft cover 22 are also part of the flow path.
The compressed air A is introduced into the cooling device 27 via the extraction line 26 and is introduced into the cooling air flow path 19 via the cooling air line 29. At this time, the casing of the heat exchanger constituting the cooling device 27 also becomes a part of the flow path.

  At least a part of the surface forming the flow path of the gas turbine 1 is hardened at the atmospheric temperature, and at the temperature of the compressed air passing through at least a part of the surface forming the flow path when the gas turbine 1 is operated. A coating 6 (substance) that is in a softened state is applied. That is, the coating 6 is made of a material that softens at the operating temperature (operating atmosphere) of the gas turbine 1.

The coating 6 is formed on the lower portion of the flow path in the vertical direction. In other words, the coating 6 is applied to the surface of the gas turbine 1 where the space is formed above.
Specifically, the coating 6 is applied to the bottom of the combustor casing 25, the upper part of the intermediate shaft cover 22, the bottom surface of the heat exchanger constituting the cooling device 27, piping such as the extraction line 26 and the cooling air line 29. ing. That is, the coating 6 is applied to a portion where foreign matter introduced into the flow path in the gas turbine 1 is likely to adhere, that is, a lower portion in the vertical direction, or a bent portion of a pipe where the flow rate of the compressed air A becomes slow. Moreover, it is apply | coated to the site | part which is easy to generate | occur | produce rust by low temperature like the cooling system 5. FIG.

The coating 6 is appropriately selected according to the temperature during operation of the gas turbine 1 where it is applied.
For example, borate glass (low-melting glass) can be selected as the coating 6A to be applied to the bottom of the combustor casing 25 where the temperature during operation reaches 450 ° C., the top of the intermediate shaft cover 22, and the like. Boric acid glass is a substance having a covalent bond and a glass transition temperature (softening point) of about 450 ° C.

  By making the coating 6 such a covalent substance, a phase change occurs gently. That is, when heated from the solid phase, it does not become a liquid phase but becomes a glass phase (soft solid phase), so that it can be expected to soften while maintaining the coated shape.

  In addition, a part around the cooling system 5 where the temperature during operation is from 100 ° C. to 200 ° C., such as the bottom surface of the cooling device 27 (heat exchanger), the inertia filter collision surface, the extraction line 26 and the cooling air line 29, etc. The coating 6B to be applied to a pipe or the like is preferably an organic polymer compound having a softening point of about 150 ° C. As the organic polymer compound, for example, materials such as polyvinyl chloride, polyvinylidene chloride, PET, and 6 nylon can be employed.

  According to the above embodiment, in the gas turbine 1 in operation, even when foreign matter such as rust generated in the compressor 2 is mixed in the flow path of the gas turbine 1, the coating 6 in which the foreign matter is in a softened state. Can be adsorbed and retained on the surface. That is, the foreign matter that has flowed through the flow path is held by the coating 6 that is in a softened state at the operating temperature of the gas turbine, thereby preventing problems caused by the foreign matter. When foreign matter such as rust comes out to a portion where there is a space and the flow velocity is slow, such as the upper part of the vehicle compartment 25 and the intermediate shaft 21, the foreign matter is adsorbed to the coating 6 during the precipitation because it once settles from its own weight.

Moreover, compared with filtration apparatuses, such as a filter, a foreign material can be collected, without producing pressure loss.
Moreover, since there is no need for an installation place, it can be introduced into an existing plant at low cost.

  Further, since the coating 6 is in a cured state at the atmospheric temperature, the operation can be performed without causing any trouble during the maintenance operation of the gas turbine 1. Moreover, since it is easy to peel the coating 6 if it is a hardening state, the work efficiency of a maintenance work can be improved.

  Further, since the coating 6 is a covalent substance that becomes softened by glass transition at the operating temperature of the gas turbine 1, the coating 6 does not become a liquid phase when heated from the solid phase, but a glass phase (soft solid Therefore, it can be softened while maintaining its shape.

Further, by making the coating 6A a low-melting glass having a softening point of about 450 ° C., foreign matter can be adsorbed at a portion exposed to the high-temperature compressed air A.
Further, by making the coating 6B an organic polymer compound equivalent to the compressed air A having a softening point cooled, foreign matter can be adsorbed at a portion exposed to the cooled compressed air A.

The embodiments of the present invention have been described in detail with reference to the drawings. However, additions, omissions, substitutions, and other modifications can be made without departing from the spirit of the present invention. Further, the present invention is not limited by the embodiments, and is limited only by the scope of the claims.
For example, in the above-described embodiment, an example in which only the low-melting glass is applied to a portion exposed to high-temperature compressed air has been described. However, an organic polymer compound may be applied on the low-melting glass. By setting it as such a structure, the coating which becomes a softened state in a wide temperature range can be provided.

DESCRIPTION OF SYMBOLS 1 Gas turbine 2 Compressor 3 Combustor 4 Turbine 5 Cooling system 6 Coating (material)
DESCRIPTION OF SYMBOLS 7 Compressor rotor 8 Compressor casing 9 Compressor rotor axial part 10 Compressor rotor blade 11 Compressor stationary blade 13 Turbine rotor 14 Turbine casing 15 Turbine rotor axial part 16 Turbine rotor blade 17 Turbine stationary blade 19 Cooling air flow path 20 Generator 21 Intermediate shaft 22 Intermediate shaft cover 24 Combustor casing 25 Combustor casing 26 Extraction line 27 Cooling device 28 Filter 29 Cooling air line A Compressed air G Combustion gas

Claims (5)

A gas turbine in which compressed air of a predetermined temperature moves through an internal flow path during operation,
At least a part of the surface forming the flow path is coated with a substance that is hardened at the atmospheric temperature and softened at the temperature of the compressed air that passes through the part during operation of the gas turbine. A gas turbine characterized by.   The gas turbine according to claim 1, wherein the substance is a covalently bonded substance that is softened by glass transition at an operating temperature of the gas turbine.   The gas turbine according to claim 2, wherein the substance is low-melting glass.   The gas turbine according to claim 2, wherein the substance is an organic polymer compound. The gas turbine has a cooling system for cooling at least a portion of the turbine;
The gas turbine according to claim 3, wherein the substance applied to the flow path through which the compressed air cooled by the cooling system flows is an organic polymer compound.

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