JPS59183003A - Seal device for stationary blades in fluid machinery - Google Patents

Abstract

PURPOSE:To reduce the leakage volume of cooled air by a method wherein a seal plate arranged between the adjoining static vane segments is formed by a connection between the two metallic plates having different coefficients of thermal expansion. CONSTITUTION:Grooves 6 are formed at the circumferential adjoining surfaces of end walls 1 and 2 of static vane segment and seal plates 9 are inserted into the grooves 6. The seal plates 9 are formed by connecting two metallic plates having different coefficients of thermal expansion. As a temperature of the seal plates is increased, the seal plate 9 are thermally deformed to show the projected shape and to contact with the grooves 6, so that it is possible to reduce the volume of leakage of cooled air for the flowing fluid.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a sealing device that prevents cooling air from leaking into a working fluid side in a stator vane portion of a fluid machine such as a gas turbine or a steam turbine.

[Prior art]

For example, in a gas cylinder, as shown in Figs. 1 and 2, a stator is made up of an outer end wall 1, an inner end wall 2, and a plurality of stator blades 3 fixedly installed between the end walls. A plurality of blade segments are arranged in the circumferential direction inside the casing 4 to form an annular stationary blade portion. The valley vane segment is attached to the casing 4 with the outer peripheral surface of the outer end wall 1 in contact with the inner surface of the casing 4.

By the way, in the stationary blade section of the gas turbine, each station x
Tohigment thermally expands because it is directly exposed to high-temperature working gas during gas turbine operation. Thermal expansion of this stationary vane segment is large in the circumferential direction because it is restrained in the radial direction by the relatively low temperature casing 4. Therefore, when assembling, each rip
Said circumferential thermal expansion f l! between the blade segments! Each stator vane segment is arranged with a gap 5 for accommodating the stator blade. However, in this state (1), the cooling air leaks into the working gas side through the gap 5, causing a decrease in the temperature of the working gas, which in turn causes a decrease in the thermal efficiency of the gas turbine.
Generally, a sealing device is provided between each stationary vane segment to prevent cooling air from leaking into the working gas side.

Conventional sealing devices, as shown in FIGS. 1 to 3, have a l? Grooves 6 are provided on the circumferentially adjacent surface of the outer end wall 1 and the circumferentially adjacent surface of the inner end wall 2, and a seal plate 7 made of one metal plate is inserted into each groove 6. , and a gap 8 is provided on a surface adjacent to the seal plate 7 and the groove 6 in the circumferential direction to allow the sole plate 7 and the stationary blade segment to thermally expand in the circumferential direction without being restrained by each other. It becomes.

However, in the above-mentioned sealing device, for example, when looking at the outer end wall portion of each stator vane segment, the third
As shown by the arrows in the figure, a small amount of cooling air leaks to the working gas side through the gaps 5 between the stator vane segments and the gaps 8 between the sole plates 7 and the grooves 6. This leakage of cooling air to the working gas side also occurs at the inner end wall portion of each stationary vane segment.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a sealing device for a stator vane in a fluid machine that has a high sealing effect and can minimize the amount of cooling air leaking to the working fluid side.

[Summary of the invention]

In order to achieve this object, the sealing device of the present invention uses a sealing plate formed by joining two types of metal plates with different coefficients of linear expansion as the sealing plate. A contact portion is formed between the sealing plate and the inner surface of the groove by thermal deformation of the groove.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 4 and 5. FIG. 4 is a cross-sectional view of the stationary part of a gas turbine equipped with the sealing device of the present invention 1, and FIG. 5 is a cross-sectional view showing the sealing portion of the inner end wall portion of the stator vane segment in the sealing device of the present invention. It is.

In the drawings, the same reference numerals as in FIGS. 1 to 3 indicate the same or equivalent parts. The sealing device of the present invention uses two types of metal plates 9 having different +lSj shadow expansion coefficients as the sealing plates inserted into the grooves 6.
A seal plate 9 in which A and 9B are joined is used.

The two metal plates facing the working gas side in the seal plate 9 are IF! 3 #3! The metal plate 9B facing the cooling air 1 IO is made of metal with a low expansion coefficient.

However, in the sealing device 11'' of the present invention, when the v11 person in the sealing portion rises due to the operation of the gas turbine,
For example, when looking at the seal plate 9 that seals the inner end wall 2 portions of each static segment shown in FIG.
As shown in the figure, it is thermally deformed into a convex shape and comes into contact with the inner surface of the groove 6.

Since the contact portion between the seal plate 9 and the groove 6 is a surface contact, the amount of leakage of cooling air to the working gas side is extremely reduced. Further, also in the seal portion of the outer end wall 1 of each stationary vane segment, the seal plate 9 is thermally deformed and comes into contact with the inner surface of the groove 6, so that the same sealing effect as described above can be obtained.

In addition, when the amount of leakage of cooling air to the working gas side was measured using the sealing device of the present invention, it was found that
It was confirmed that the

It should be noted that the sealing device of the present invention is not limited to sealing only the static bar section of a gas turbine, but can of course be applied to the stationary vane section of a fluid machine such as a steam turbine.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to provide a sealing device for a tt% i side portion of a γ4 body machine, which has a high sealing effect and can minimize the amount of leakage of cooling air to the working fluid side.

[Brief explanation of drawings]

Fig. 1 is an IUi side view showing the stationary part of a gas turbine equipped with a conventional sole device, Fig. 2 is a perspective view of the stationary blade section in Fig. 1, and Fig. 3 is a conventional seal. 4 to 6 show an embodiment of the present invention, and Fig. ε34 shows the sealing device of the present invention at
FIG. 5 is a cross-sectional view showing the entire stationary part of the gas turbine obtained, FIG.
The seal plate shown in the figure shows a thermally deformed state.
It is a front view. 1...Outer end wall, 2...Inner end wall, 3...V'H<, 4...Casing, 6...
・ηL 9...) No. t Fzl No. 2 M Haku 3 M House ω diagram ￥ 5 diagram G diagram

Claims (1)

[Claims] 1. Stator consisting of an arc-shaped outer end wall, an inner end wall, and a plurality of stator blades fixedly installed between both end walls. 2. A plurality of segments are arranged in the circumferential direction inside the casing to form an annular shape. Cooling q=air working fluid 1i111 is formed between adjacent stator vane segments.
The sole device is provided with a groove provided in the circumferentially facing surface of the outer end wall and the circumferentially facing surface of the inner end wall in the circumferential direction. With the seal plate inserted into each groove (in a fluid machine that makes noise, a seal plate made by joining two types of metal plates with different coefficients of linear expansion is used as the seal plate, A sealing device for a static g section in a fluid machine, characterized in that a contact portion is formed between the knoll plate and the inner surface of the groove by thermal deformation of the seal plate.