JP2000045793A - By-pass valve of gas turbine combustor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent foreign matters from intruding into a gas turbine from a by-pass duct when a by-pass valve is opened, in the by-pass valve of a gas turbine combustor. SOLUTION: A fixed ring 2 is mounted on an inlet of a by-pass duct 19 of a gas turbine combustor. A plurality of by-pass ducts 19 are circumferentially mounted among the cabins around the rotor of a gas turbine, and their duct inlets are mounted on the annular fixed rings 2. The annular movable rings 3 are rotatably mounted in the fixed rings 2 through the guide rollers 4, the movable rings 3 comprise the by-pass valves on the positions corresponding to the openings of the by-pass ducts 19, the movable rings 3 are rotated in the low load and the openings of the ducts 19 are opened to introduce the air. A porous plate 1 is mounted on the end surfaces 2a, 2b of the fixed ring 2 to cover the total periphery of the by-pass valve, so that the air flows in from the holes of the porous plate 1 and the intruding of the foreign matters can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bypass valve for a gas turbine combustor, and more particularly to a gas turbine combustor by-pass valve for preventing foreign matter from entering into the interior of the gas turbine combustor together with air and damaging moving blades and vanes of the gas turbine. It is about preventing.

[0002]

2. Description of the Related Art FIG. 5 is an overall view showing a combustor of a gas turbine. In the figure, a combustor 10 is housed in a vehicle interior 22. 11 is a main fuel inlet, 12 is a pilot fuel inlet, 13 is a main nozzle, a plurality of nozzles are arranged around the main nozzle, and the main fuel is supplied from the main fuel inlet 11,
Burn. Reference numeral 14 denotes a pilot nozzle, which is disposed at the center of the main nozzle, and is for supplying pilot fuel from the pilot fuel inlet 12 to ignite the main fuel. Reference numeral 15 denotes an inner cylinder through which the high-temperature combustion gas burned by the main nozzle 13 flows, and 16 denotes a transition piece, which sends the high-temperature combustion gas flowing from the inner cylinder 15 to the combustion gas passage of the gas turbine 21, Here, work is performed to rotate the rotor of the gas turbine. The gas turbine combustor is generally referred to as a combustor constituting a nozzle portion, including an inner cylinder and a transition piece ahead of the combustor.

[0003] Reference numeral 17 denotes a compressor, which allows compressed air to flow out of an air outlet 18 into a vehicle compartment 22, and the air is supplied to the combustor 10.
Flows into the combustion chamber from the nozzle section and is provided for combustion. 1
Reference numeral 9 denotes a bypass duct, which allows air to flow into the transition piece 16 from inside the cabin 22. Reference numeral 20 denotes a bypass valve at the entrance of the bypass duct 19. When a small amount of combustion air is sufficient at a low load or the like, the valve is opened to release excess air to the gas path side in order to improve the combustion state, and the bypass valve is opened. It operates so that air flows into the transition piece 16 and closes when rated.

In the combustor having the above structure, air from the compressor 17 is introduced from the nozzle portion, and the main fuel from the main nozzle 13 is ignited by the pilot nozzle 14 and burned to generate high-temperature combustion gas. Gas is inner cylinder 1
After passing through 5, the gas is sent from the transition piece 16 to the gas turbine 21 to perform work. However, air is mixed in the combustion of the fuel to form a premixed air so that the fuel is burned. For this reason, when the fuel is low at low load, the flame goes out and the high temperature combustion gas is not generated enough. The bypass valve 20 is opened instead, and excess air is discharged from the bypass duct 19 to the gas path from the transition piece 16. In addition, at the time of rating, the bypass valve 20 is closed so as to perform combustion using normal premixed fuel.

When the bypass valve 20 is opened and air is guided from the bypass duct 19 to the transition piece 16, foreign matter may enter the bypass valve 20 and damage the gas turbine. That is, the support of the combustor piping is damaged by vibration, the bolts and nuts are dislodged and scattered, and these enter the bypass duct 19, are sent to the gas turbine 21, and are sent to the moving blades and stationary blades of the turbine. May cause serious damage. In the conventional gas turbine combustor, no measures have been taken to prevent foreign matter from entering when the bypass valve is opened.

[0006]

As described above, in the conventional gas turbine combustor, the bypass valve 20 is opened when the load is low or the like, but at this time, the pipe support members and the like are fatigued due to vibration during operation. When broken, the metal pieces may fly and enter the bypass duct 19 from the bypass valve 20. Similarly, the combustion vibration may cause the bolts and nuts to loosen and scatter from the fixed portion, or a measurement sensor or the like may be sucked. In such a case, these intruders enter the combustion gas passage of the gas turbine 21 via the bypass duct 19, the inner cylinder 15, and the transition piece 16 and collide with the moving blades and the stationary blades, thereby causing serious damage. There is. Conventionally, such measures have not been taken, and with the recent rise in temperature of gas turbines, it has become necessary to give due consideration to such dangers.

Accordingly, the present invention prevents foreign matter from entering the bypass valve of the gas turbine combustor, and prevents foreign matter from entering the bypass valve during operation without impairing the function of the bypass valve. It is an object of the present invention to provide a bypass valve for a gas turbine combustor which prevents damage to the rotor and stationary blades of a turbine due to collision of foreign matter.

[0008]

The present invention provides the following means (1), (2) and (3) to solve the above-mentioned problems.

(1) A gas turbine combustor having an air bypass duct and a bypass valve provided at the inlet of the air duct, wherein a perforated plate is arranged before or after the bypass valve. Bypass valve.

(2) The bypass valve according to (1), wherein the perforated plate is made of punched metal.

(3) The bypass valve for a gas turbine combustor according to the above (1), wherein the perforated plate covers a front surface of the bypass valve.

In (1) and (3) of the present invention, since the perforated plate is disposed before or after the bypass valve, when the bypass valve is opened and air is introduced into the combustor, the air is supplied to the plurality of perforated plates. However, foreign matter such as metal pieces, bolts, nuts, etc., is smaller than these foreign matters, for example, 1 hole.
If a hole with a size of 0 mm or less is provided, it cannot enter. Therefore, these metal pieces, bolts and nuts do not enter the combustion gas passage of the gas turbine, and the gas turbine can be safely operated. Also, (2)
As described above, a punching metal can be used as the perforated plate.

[0013]

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a cross-sectional view showing a state in which, for example, a perforated plate for preventing foreign matter from entering is attached to a bypass valve of a gas turbine combustor according to an embodiment of the present invention, for example, a punched metal, FIG. 2 is a front view of the punched metal, and FIG. FIG. 9 is a front view showing another application example of the punching metal.

In FIG. 1, reference numeral 19 denotes a bypass duct connected to the combustor, the inlet of which is attached to the fixing ring 2. This bypass duct 19 is connected to the combustor. Reference numeral 3 denotes a movable ring that opens and closes, and is disposed in the fixed ring 2. When the movable ring 3 rotates, the opening provided in the movable ring 3, that is, the opening of the bypass duct 19 is opened and closed by a bypass valve. It is supposed to. Refer to FIG. 4 for the overall arrangement.

Reference numeral 4 denotes a guide roller which rotatably supports the movable ring 3. Reference numeral 1 denotes a perforated plate which is a feature of the present invention, for example, a punching metal, which is attached to the end surfaces 2a and 2b of the fixed ring 2 with bolts 5 and covers the front surface of a bypass valve which is an opening of the movable ring 3. . The perforated plate 1 is provided with a number of holes having a diameter such that air can flow without resistance and metal pieces, bolts, and nuts cannot pass therethrough. The shape of the hole may be circular or elliptical, an elongated slit, or a mixture of these. When a thickness is required, a perforated metal plate is used.

FIG. 2 is a front view of the punching metal 1. Reinforcing ribs 1a, 1b, and 1c are attached to the metal plate by molding or welding for vibration resistance. A large number of holes 6 are densely formed in the surface of the metal plate. A number of holes are drilled. The material of the punching metal 1 is the same as that of the bypass valve 20, and the plate thickness is about 5 mm.
The diameter of the hole 6 is about 10 mm where no foreign matter enters and the pitch is also about 10 to 13 mm. The size of the punching metal 1 is determined by the capacity of the gas turbine plant, the diameter of the movable ring 3 is different, and is determined by the capacity. It is. Reference numeral 5a denotes a bolt hole for attaching to the end faces 2a and 2b of the fixing ring 2 with bolts 5 as shown in FIG.

FIG. 3 shows another example of a punching metal.
The size and the shape are the same as those of the example of FIG. 2, but many reinforcing ribs are provided to improve the vibration resistance. The punching metal 7 is provided with a plurality of ribs 6b, 6c, 6d, 6e, 6f orthogonal to the reinforcing ribs 6a. In the example of FIG. 1, two ribs 1c and 1b are provided. I have.

FIG. 4 is a front view showing the entire arrangement of punching metal as an example for common arrangement of bypass valves in the entire vehicle cabin, and is a view of the combustor side from the gas turbine combustion gas passage side. As shown in the figure, the punching metal 1 or 7 is attached to the end face of the fixed ring 2 so as to cover the entire circumference of the circular fixed ring 2. In the example, the number of sheets corresponding to one to one is arranged all around.

The number and shape of the punching metal are not limited to the examples shown in FIGS. 2 and 3, but may be several continuous arcuate shapes. A plurality of adjacent bypass valves 20 may be covered, which is appropriately determined according to conditions such as strength and vibration conditions.

The perforated plate may be mounted either before or after the bypass valve, which has the effect of preventing foreign matter from entering the combustor. Mounting the perforated plate in front of the bypass valve will not damage the valve due to foreign matter. It is also relatively convenient for removing foreign matter.

In the gas turbine combustor having the above structure,
At the time of rated operation of the gas turbine, the inlet opening of the bypass duct 19 is closed by the bypass valve 20. However, when the amount of fuel is small such as when the load is low, the flame of the nozzle may be lost if the amount of combustion air is large. Therefore, the amount of premixed air for combustion is reduced, and instead, the bypass valve 20 is opened, and the air is discharged from the bypass duct 19 through the transition piece 16. In this case, in the illustrated example, the movable ring 3 is rotated by a drive mechanism (not shown) so as to pass through an opening provided in the movable ring 3, that is, the opening of the bypass valve 20 and the bypass duct 19.

In this case, air flows from the hole 6 of the punched metal 1 or 7 through the bypass valve 20 to the bypass duct 1.
The foreign matter that flows into the transition piece 9 and is guided into the transition piece 16, and that tries to enter the bypass duct 19 together with the air is prevented from entering by a large number of holes. Therefore, safe operation can be performed without foreign matter entering the combustion gas passage of the gas turbine.

In the present embodiment, the bypass valve 20 rotates the movable ring 3 so that the bypass duct 19
In the above description, the punching metal 1 or 7 is applied to a combustor having a bypass duct of a type that opens and closes an opening of the bypass duct. However, a type in which a bypass valve provided at an inlet of the bypass duct is rotated to open and close the bypass duct. It can be naturally applied to the combustor of the above, and has the same effect.

[0024]

According to the present invention, there is provided a gas turbine combustor having a bypass valve for air and a bypass valve provided at an inlet of the duct.
The basic feature is that a perforated plate is arranged so as to cover the front or rear surface of the bypass valve. As a result, even if air is introduced by opening the bypass valve, foreign matter does not enter, and damage to the moving blades and stationary blades of the gas turbine due to entry of foreign matter can be prevented, so that the gas turbine can be safely operated. .

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an attached state of a bypass valve of a gas turbine combustor according to one embodiment of the present invention.

FIG. 2 is a front view of a punched metal according to one embodiment of the present invention.

FIG. 3 is a front view showing another application example of the punching metal according to the embodiment of the present invention.

FIG. 4 is an overall front view of a gas turbine combustor according to one embodiment of the present invention, in which a foreign matter intrusion prevention punching metal is attached to a bypass valve.

FIG. 5 is a general layout of a gas turbine combustor.

[Explanation of symbols]

1,7 Punched metal 1a, 1b, 1c Reinforcing rib 2 Fixing ring 3 Movable ring 5 Bolt 5a Bolt hole 6 Hole 6a, 6b, 6c, 6d, 6e, 6f Reinforcing rib 10 Combustor 19 Bypass duct 20 Bypass valve

Claims (3)

[Claims] 1. A gas turbine combustor having an air bypass duct and a bypass valve provided at an inlet of the air duct, wherein a perforated plate is disposed before or after the bypass valve. valve. 2. The bypass valve according to claim 1, wherein the perforated plate is made of punched metal. 3. The bypass valve according to claim 1, wherein the perforated plate covers a front surface of the bypass valve.