JPH04107403U - Steam turbine high and medium pressure casing - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent thermal deformation of the inner vehicle compartment. [Structure] A hole 17 (or pipe) provided in the inner casing 8 connects the air bleed port 16 in the high pressure section blade row 4 to the inner casing 8 and the outer casing 5.
It communicates with the gap 9 between. As a result, part of the steam in the bleed port 16, which has a higher temperature than the steam in the gap 9, is transferred to the gap 9.
Injected into the interior of the vehicle to suppress excessive cooling on the outside of the interior of the vehicle,
Prevent thermal deformation.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to the structure of a steam turbine high and intermediate pressure casing.

0002

[Conventional technology]

FIG. 2 shows the structure of a conventional steam turbine high and intermediate pressure casing. In Figure 2, the steam is , flows from the high-pressure inlet pipe 1 through the high-pressure inlet section 2 to the governor stage 3, and is introduced to the high-pressure section blade row 4. It will be destroyed. The steam that has flowed out of the high-pressure blade row 4 is then guided outside the outer casing 5 and recycled. After being heated, it flows into the medium pressure blade row 7 through the medium pressure inlet pipe 6.

0003 In addition, some of the steam that has flowed out of the high-pressure blade row 4 is transferred between the high-pressure inner casing 8 and the outer casing 5. Passing through the gap 9, from the nozzle 10 provided in the high pressure inner casing 8 adjacent to the medium pressure inlet part 11. It flows into the shield internal space 12. This inflow steam is then transferred to the outer compartment 5 and the It merges into the medium pressure inlet part 11 through the slit 14 provided between the multi-shield plate 13 After passing through the intermediate pressure blade row 7 together with the reheated steam, it flows out of the cabin from the exhaust chamber 15. Ru. Furthermore, within the high-pressure section blade row 4 described above, a portion of the steam flows outside through the bleed port 16. The air is extracted.

0004 Note that a part of the steam that has flowed out of the high-pressure blade row 4 is transferred to the gap 9 between the inner casing 8 and the outer casing 5. The steam that flows out of the high-pressure section blade row 4 is passed through the high-pressure section blade row 4 and the steam inside the high-pressure section blade row 4 and reheated. This is to prevent the temperature of the outer compartment 5 from rising by taking advantage of the fact that the temperature is lower than that of steam.

[0005]

[Problem that the idea aims to solve]

By the way, in the structure of the conventional steam turbine high and medium pressure casing described above, Steam flowing out from the high-pressure blade row 4 flows into the gap 9 between the chamber 5 and the inner casing 8. It is cooled down more. At this time, the steam in the high-pressure blade row 4 and the outer casing 5 and inner casing 8 If the temperature difference between the gap 9 and the gap 9 is large, there is a problem that the inner compartment 8 is thermally deformed.

[0006] This invention was devised to solve the problems of the conventional technology. The purpose is to provide a high-medium pressure casing for a steam turbine that can effectively prevent thermal deformation of the casing. shall be.

[0007]

[Means to solve the problem]

In order to solve the above problems, the present invention has been developed in the high and medium pressure casing of a steam turbine. , the air bleed port in the high-pressure blade row is communicated with the gap between the inner and outer casings.

[0008]

[Effect]

According to the above means, the air bleed port in the high-pressure section blade row is communicated with the gap between the inner casing and the outer casing. By doing so, the steam inside the bleed port is hotter than the steam in the gap between the inner and outer compartments. A portion of the steam is injected into the gap between the inner and outer compartments, thereby eliminating excess water on the outside of the inner and outer compartments. It suppresses cooling and prevents thermal deformation of the interior of the vehicle.

[0009]

【Example】

Hereinafter, one embodiment of the present invention will be described in detail with reference to FIG. Figure 1 is Figure 2 2 is a partially enlarged diagram for explaining the present invention, and the overall configuration is similar to that shown in FIG. 2. Since this is the same as the previous one, duplicate explanation will be omitted.

0010 In FIG. 1, a bleed air is provided in the high pressure blade row 4 to bleed part of the steam to the outside. According to this embodiment, the opening 16 connects the inner compartment 8 and the outside via the hole 17 formed in the inner compartment 8. It is communicated with a gap 9 between the vehicle compartment 5 and the vehicle compartment 5.

[0011] In this way, the air bleed port 16 in the high pressure blade row 4 is located in the gap 9 between the inner casing 8 and the outer casing 5. By communicating through the hole 17, the steam in the gap 9 between the inner compartment 8 and the outer compartment 5 is A portion of the steam in the bleed port 16, which is relatively high temperature, is passed through the communication hole 17 to the inner compartment 8 and the outer compartment Injected into the gap 9 with the chamber 5, this suppresses excessive cooling of the outside of the inner vehicle chamber 8 and cools the inner vehicle interior. No. 8 thermal deformation can be prevented.

0012 In addition, instead of the communication hole 17 in the embodiment described above, a communication pipe is used to connect the air bleed port 1. 6 may be communicated with a gap 9 between the inner compartment 8 and the outer compartment 5.

[0013]

[Effect of the idea]

As described above, according to the present invention, high- and intermediate-pressure casings of steam turbines By communicating the air bleed port in the pressure section blade row with the gap between the inner and outer casings, the inner and outer casings are A portion of the steam in the bleed port, which is hotter than the steam in the gap with the outer car compartment, is transferred to the inner and outer car compartments. Injected into the gap between the inside and outside of the car, this suppresses excessive cooling of the outside of the inside of the car and prevents thermal changes in the inside of the car. It has an excellent effect of preventing the mold from forming.

[Brief explanation of drawings]

FIG. 1 is a sectional view of essential parts showing a steam turbine high and intermediate pressure casing according to an embodiment of the present invention.

FIG. 2 is an overall sectional view showing a conventional steam turbine high and intermediate pressure casing.

[Explanation of symbols]

4 High pressure section blade row 5 Outer compartment 8 Inner compartment 9 Gap 16 Air bleed port 17 Communication hole

Claims (1)

[Scope of utility model registration request] 1. A high and intermediate pressure casing for a steam turbine, wherein an air bleed port in a high pressure section blade row is communicated with a gap between an inner casing and an outer casing.