RU2442900C2 - Steam turbine stage - Google Patents

Abstract

FIELD: steam turbines.

SUBSTANCE: steam turbine stage has diaphragm (1), rotor blades (2) with bandages (3). Bandages (3) have bandage axial comb (6) from the rim clearance (5) side. Axial comb (7) is located in the rim clearance (5) under bandage axial comb (6) creating labyrinth channel (8) with it. Axial comb (6) is made on the perimeter ring (4) installed in the rim clearance (5). Diaphragm (1) is equipped with rim (9) installed in the cage (10). The cage (10) holds above-bandage sealing (11). The cage (10) also includes water discharge channel (12) made under bandages.

EFFECT: reduction of steam turbine cost and reduction of labour intensity.

1 dwg, 1 dwg

Description

The invention relates to the field of turbine engineering and may find application in the development and manufacture of steam turbines for nuclear power plants.

A step of a steam turbine is known, comprising rotor blades with bandages and a stator part, wherein the bandages and stator part from the side of the interventional gap are made with a recess and a protrusion, respectively, and a sealing axial ring contacting the recess surface of the bandages is fixed on the stator part.

(US 6102655, F01D 11/08, published 08/15/2000)

A known step of a steam turbine, including a diaphragm, rotor blades with bandages having an axial ridge on the side of the interventional gap.

(SU 1671908, F01D 11/08, published 04.11.1989)

The closest in technical essence and the achieved technical result is the stage of the axial turbomachine containing the diaphragm, rotor blades with bandages having an axial crest on the side of the interventional gap and another sealing axial crest in the interventional gap, fixed in the rim of the diaphragm and located under the axial crest of the band of the rotor blades .

(SU 380848, F01D 11/08, published 05/15/1973)

The disadvantages of all known technical solutions is the difficulty of manufacturing, not enough high vortex power on the periphery of the interventional gap, which reduces the efficiency of the stage.

The objective of the invention and the technical result of the invention is to increase the efficiency of the steam turbine stage and reduce the complexity of its manufacture.

The technical result is achieved by the fact that the step of the steam turbine contains a diaphragm (1), rotor blades (2) with bandages (3) having an axial ridge (6) of bandages from the side of the interventional gap (5) and an axial ridge (7) in the interventional gap ( 5) located under the axial ridge (6) of the bandages and forming a labyrinth channel (8) with it, and the axial ridge (6) is made on the peripheral ring (4) installed in the inter-crown gap (5), and the diaphragm (1) is provided with a rim (9) installed in the clip (10), in which the over-band seal is fixed (11), and in the clip e (10) in the area above the bandages made a drainage channel (12).

The invention can be illustrated by the data presented in the figure, where:

1 - aperture;

2 - working blades;

3 - bandage;

4 - peripheral ring;

5 - interventional clearance;

6 - axial crest of the bandage;

7 - axial ridge forming a labyrinth channel;

8 - labyrinth channel;

9 - aperture rim;

10 - clip;

11 - over-seal;

12 - dehumidification channel.

The device according to the invention operates as follows.

Steam from the diaphragm (1) is directed to the working blades (2). Under the action of the pressure difference, part of the vapor passes through the labyrinth channel (8), the over-seal seal (11) and the moisture removal channel (12). The labyrinth channel (8) and the device elements behind it create significant aerodynamic drag, as a result of which the steam flow outward decreases, and the efficiency of the steam turbine stage increases.

The peripheral ring plays the role of a displacer and is located in the place where a vortex could have arisen if there were no ring. In this case, the peripheral ring, as well as other elements of the composite diaphragm, are much smaller than the monolithic stator part in the closest analogue, which significantly reduces the complexity of manufacturing the stage when fitting the sealing ridges.

Thus, the use of a steam turbine device according to the invention ensures the achievement of the technical result.

Claims (1)

A steam turbine stage containing a diaphragm (1), rotor blades (2) with bandages (3) having an axial ridge (6) of bandages from the side of the interventional gap (5) and an axial ridge (7) in the interventional gap (5) located under axial ridge (6) of the bandages and the labyrinth channel forming with it (8), characterized in that the axial ridge (6) is made on the peripheral ring (4) installed in the inter-crown gap (5), and the diaphragm (1) is provided with a rim (9) ) installed in the clip (10), in which the over-band seal is fixed (11), and in the clip (10) in the area above the bandages in A water drain channel (12) has been completed.

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