JPH08338632A - Driving device for adjusting mechanism for air flow rate of gas turbine - Google Patents

Abstract

PURPOSE: To control air flow rate supplied to respective combustion devices so as to be completely uniform by simultaneously driving the air flow adjusting mechanisms of the gas turbine combustor by means of a control ring. CONSTITUTION: Air flow rate adjusting mechanisms are connected to a control ring 6 provided on the outer periphery of a casing through link mechanisms. An actuator 12 is operated so that the control ring 6 and the air flow rate adjusting mechanisms are driven. The control ring 6 is supported by support ring rollers 8 provided on the outer periphery of the casing. A support ring is freely supported at two right and left points on the casing, freely and horizontally able to slip and is supported at upper and lower points by means of pins. Thus, the center of the support ring is not deviated from the center of the casing and the support ring can be freely diametrically deformed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive device for an air flow rate adjusting mechanism.

[0002]

2. Description of the Related Art In a low NOx combustor of a gas turbine, it is necessary to adjust the fuel flow rate and the air flow rate according to the load change, and there is a method for adjusting the air flow rate as shown in JP-A-61-195214. . Further, the gas turbine is usually a multi-cylinder system having a plurality of combustors, and it is necessary to control the air flow rate of each combustor to be constant in order to stabilize the combustion of all the combustors. A method for simultaneously driving the air flow rate adjusting mechanisms of a plurality of combustors at once is disclosed in JP-A-61-1952.
As disclosed in Japanese Patent Publication No. 14, a roller is provided on the outer periphery of the casing to support the control ring and operate the control ring.

[0003]

However, during operation of the gas turbine, the temperature of the gas turbine casing becomes high, so that the casing expands in the radial direction. The gap between the rollers supporting this changes, and the core of the control ring deviates from the core of the casing. This eccentricity affects the opening area of the air supply port through the link mechanism, and the air flow rate becomes uneven in each combustor. There was a drawback.

An object of the present invention is to provide a drive device for controlling the air flow rate adjusting mechanism so that the air flow rate supplied to each combustor becomes constant under any temperature condition.

[0005]

The air flow rate adjusting mechanism of each combustor is connected to a control ring provided on the outer periphery of the gas turbine casing through a link mechanism,
By operating the control ring in the casing circumferential direction, the control rings are simultaneously driven all at once. The feature of the present invention resides in that the roller supporting the control ring is fixed to a support ring provided on the outer periphery of the gas turbine casing and freely supported by the gas turbine casing. The support ring is freely supported by a horizontally slidable metal at the right and left central portions of the gas turbine casing, and the weights of the support ring and the control ring are applied to these two points. By supporting the upper and lower sides of the support ring with the casing and pins, the support ring core is prevented from moving horizontally with respect to the casing core, and the support ring moves axially with respect to the casing. A plurality of supports are added so that there is no twist, and the support ring allows the casing to be deformed only in the radial direction.

[0006]

[Operation] Even when the casing becomes hot during the operation of the gas turbine and the casing expands in the radial direction, and the radial expansion of the support ring is smaller than the expansion of the casing, the support ring is supported by the horizontal part and the upper and lower parts of the casing. Therefore, the core of the support ring and the core of the casing always match. Since the temperature difference between the support ring and the control ring is very small, there is no difference in elongation between the control ring and the support ring supported by the rollers fixed to the support ring, and there is no eccentricity. Therefore, the operation of the control ring can be uniformly transmitted to the link mechanism arranged on the outer periphery of the casing without causing the cores of the control ring and the casing to be displaced, and the air flow rate adjusting mechanism of each combustor can be operated uniformly. is there.

[0007]

1 is a side view of a gas turbine showing an embodiment of the present invention.

The gas turbine is roughly divided into a compressor 1, a combustor 2 and a turbine 3. Combustor 2
Is attached to the circumference of the wrapper casing 4 and a lever 5 for driving the air flow rate adjusting mechanism projects from each combustor 2. The control ring 6 provided on the outer periphery of the wrapper casing 4 is connected to the lever 5 of each combustor to operate the control ring 6, thereby driving the air flow rate adjusting mechanism to adjust the air flow rate of the combustor 2. The support ring 7, which is a feature of the present invention, is freely supported by the wrapper casing 4 and supports the control ring 6 by a plurality of rollers 8.

FIG. 2 is a view taken along the line AA of FIG. 1, and is a front view of the control ring 6 and the support ring 7. 3 is a view taken along the line BB of FIG. 2, and is a cross-sectional view of the control ring 6 and the support ring 7. The control ring 6 and the support ring 7 are attached to the outer periphery of the casing 4 concentrically with the casing 4. However, as shown in FIG. 3, the control ring 6 and the support ring 7 have substantially the same diameter, so that the support ring is shown in FIG. 7 is hidden behind the control ring 6. Support ring 7
Are freely supported by lubricous metals 9a and 9b attached to the left and right of the casing 4, and the support ring 7 can slide horizontally by this supporting portion. The upper and lower sides of the support ring 7 are supported by the casing 4 by the center pins 10a and 10b.
The core and the core of the casing 4 are prevented from shifting in the horizontal direction. Further, several supports 11 are provided to prevent the support ring 7 from moving and twisting in the axial direction. The support portions of these support rings 7 are not constrained, and the support rings 7 can be freely deformed in the radial direction. Several rollers 8 are fixed to the support ring 7, and the control ring 6 is supported by the rollers 8. The rollers 8 and the control ring 6 have grooves as shown in FIG. 3 in order to prevent axial movement and twist of the control ring 6. The control ring 6 is connected to an actuator 12 such as a hydraulic cylinder or a servomotor by a rod 13, and moves in the circumferential direction along the roller 8 as the actuator 12 operates.

FIG. 4 is a sectional view of a combustor showing only a portion related to an air flow rate adjusting mechanism in a typical low NOx combustor. The compressed air 14 consists of a combustor outer cylinder 15 and an inner cylinder 16
A premixed flame is formed in the rear combustion chamber 19 together with the fuel ejected from the secondary fuel nozzle 18 through the space between them and the air supply port 17. It is the control ring 20 provided on the outer periphery of the inner cylinder 16 that adjusts the secondary air flow rate by changing the opening area of the air supply port 17, and the leaf spring 21 partially fixed to the combustor outer cylinder 15. It is supported by and operates in the axial direction of the combustor. The control ring 20 is connected to the lever 5 fixed to the outer cylinder 15 by a shaft 22, and the control ring 20 can be operated by moving the lever 5 around the shaft 22 in the axial direction of the combustor. The lever 5 is arranged in each combustor so that it faces away from the center of the casing.

The control ring 6 that moves in the circumferential direction and the lever 5 that moves in the axial direction with respect to the casing 4 are
They are connected by a link mechanism as shown in FIG. The control ring 6 and the lever 5 are connected to an L lever 23 fixed to the casing 4 via turn buckles 24a and 24b, respectively, and the L lever 23 rotates about a shaft 25 so that the control ring 6 is displaced in the circumferential direction. Is converted into an axial displacement of the lever 5. Further, the relative positions of the control ring 6, the L lever 23, the lever 5, and the air flow rate adjusting mechanism are arranged to be the same in each combustor, and the operation of the control ring 6 is the air flow rate adjusting mechanism of each combustor. So that it can be evenly transmitted to the movement of.

FIG. 6 illustrates the deformation of the casing 4, the control ring 6, and the support ring 7 due to heat generated during the operation of the gas turbine. The solid line shows the gas turbine stopped and the dotted line shows the operation. When the gas turbine is stopped, the cores of the casing 4a, the control ring 6a, and the support ring 7a are adjusted so that they are all aligned. As the load on the gas turbine increases, the temperature of the casing 4 rises and the casing 4b expands in the radial direction. The control ring 6b and the support ring 7b also expand in the radial direction, but since the temperature is lower than that of the casing 4b, it does not extend as much as the casing 4b, and the distance between the casing 4b and the support ring 7b decreases as the load increases. But the support ring 7
Due to the support mechanism of the support ring 7, the upper, lower, left and right sides of the support ring 7 are only radially deformed with respect to the casing 4.
The core of b and the core of the support ring 7b are not displaced.
Further, if the gas turbine is operating normally, the temperature distribution in the upper, lower, left, and right directions is substantially constant in both the casing 4 and the support ring 7, and the casing 4b and the support ring 7 are
The intervals of b are uniform at any position of the casing 4b. There is almost no temperature difference between the support ring 7b and the control ring 6b, and the deformation of the control ring 6b is almost the same as the deformation of the support ring 7b, and the distance between the casing 4b and the control ring 6b is also the casing 4.
It deforms in a uniform state at any position of b. Therefore, the relative positions of the control ring 6 and the air flow rate adjusting mechanism are constant for all combustors even when the load changes. Therefore, the operation of the control ring 6 can uniformly drive the respective air flow rate adjusting mechanisms to uniformly control the air flow rates of all the combustors.

[0013]

According to the present invention, the air flow rate of the combustor can be uniformly controlled over the entire load zone of the gas turbine, and the combustor cannot be adjusted uniformly during operation of the air flow rate adjusting mechanism when the load changes. It is possible to completely eliminate the possibility of the unstable combustion that had occurred.

[Brief description of drawings]

FIG. 1 is a side view of a gas turbine.

FIG. 2 is a front view of a control ring and a support ring.

FIG. 3 is a sectional view of a control ring and a support ring.

FIG. 4 is a sectional view of a combustor.

FIG. 5 is an explanatory diagram of a link mechanism.

FIG. 6 is an explanatory view of thermal deformation of a support ring and a casing.

[Explanation of symbols]

6 ... control ring, 8 ... roller, 12 ... actuator.

Claims (1)

[Claims] 1. A plurality of air supply ports for supplying air into an inner cylinder of a combustor, a control ring for adjusting opening areas of the air supply ports, and an outer cylinder of the combustor supported by the control ring. A plurality of two-stage combustors having an air flow rate adjusting mechanism composed of a link mechanism for moving in the axial direction of the combustor are provided, a plurality of rollers located on the outer periphery of the casing of the gas turbine, and the combustor supported by the rollers. And a control ring that is connected by the link mechanism and the link mechanism supported by the gas turbine casing to drive the respective air flow rate adjusting mechanisms at the same time, and an actuator that drives the control ring in the circumferential direction of the gas turbine. In a drive device for an air flow rate adjusting mechanism of a gas turbine, comprising: 2 to the casing of the gas turbine by means of slidable metal
A drive device for an air flow rate adjusting mechanism of a gas turbine, wherein a support ring supported only by points is provided on the outer circumference of the gas turbine, the roller is fixed to the support ring, and the control ring is supported by the roller. .