RU2307254C1 - Nozzle box assembly for high-temperature cylinder of steam turbine - Google Patents

Abstract

FIELD: heat power engineering; turbines.

SUBSTANCE: proposed nozzle box assembly of high-temperature cylinder of steam turbine includes supply section, transient section and section delivering steam to nozzle segments. Nozzle box assembly is made up of sections welded together, supply section is made of pipe, transient section is made in form of cone changing from pipe into oval, and steam dispensing section is made of two rings, outer and inner ones, with blanks on end faces. Proposed invention provides minimum labor input and metal usage in manufacture, reduced to minimum time taken for heating nozzle box assembly owing to use of more thin walls of welded structure and, consequently, reduced time of starting of high-temperature steam turbine.

EFFECT: increased reliability and maneuverability of turbine.

4 dwg

Description

The invention relates to the field of energy, to turbine engineering.

Known nozzle boxes for a high-temperature cylinder of a steam turbine, cast, with vertical steam supply (Trukhny AD Stationary steam turbines. - M .: Energoatomizdat. 1990. P.265).

A disadvantage of the known nozzle boxes is that with such a supply, the nozzles are not uniformly filled with steam.

Known nozzle boxes for the high temperature cylinder of a steam turbine made by casting (Truhniy A.D., Lomakin B.V. Heating steam turbines and turbines. - M.: MEI Publishing House, 2002. P.265. Fig. 9.5).

This known device is the closest device of a similar purpose to the proposed combination of features and is taken as a prototype.

The disadvantage of the device adopted for the prototype, as well as the reason that impedes the achievement of the proposed technical result when using the known device of the prototype, is that it is not possible to perform relatively thin cast walls, which leads to an increase in metal consumption, and the need to manufacture models for casting makes manufacturing more expensive devices.

The analysis of the prior art by the applicant, including a search by patent and scientific and technical sources of information, as well as identification of sources containing information about analogues of the claimed invention, allowed to establish that the applicant did not find a technical solution characterized by signs identical or equivalent to those proposed.

The definition from the list of identified analogues of the prototype, as the closest technical solution for the totality of features, allowed to identify in the claimed device a combination of significant distinctive features in relation to the applicant's perceived technical result, set forth in the following claims.

The claimed technical solution allows to ensure minimal labor and metal production, and also due to the thinner walls of the welded structure to minimize the heating time of the nozzle box and, accordingly, the start-up time of the steam high-temperature turbine, which increases its reliability and maneuverability.

A nozzle box of a high-temperature cylinder of a steam turbine is proposed, including sections — supply, transition, and section distributing steam to nozzle segments, while the box is made of sections welded to each other, the supply section is made of pipe, the transition section is made in the form of a cone passing from pipe to the oval, and the section dispensing steam to the nozzle segments is made of two rings - the outer and the inner with plugs at the ends.

The invention is illustrated by drawings, where Fig. 1 shows a longitudinal section of a nozzle box, Fig. 2 is a view A from Fig. 1, Fig. 3 is a section B-B in Fig. 1, Fig. 4 is a section BB in figure 1.

The nozzle box includes an inlet section made in the form of a pipe 1, a transition section 2 made in the form of a cone passing from the pipe to an oval, and a section distributing steam to the nozzle segments made of two rings - outer 3 and inner 4 with plugs 5 on ends. The flat sections 6 of the transition section 2 are supported by the rod 7. The sections of the nozzle box are welded together.

When starting a steam turbine, steam enters the nozzle box. Thanks to the thin walls of the welded structure, it quickly warms up. The wall thickness in a welded structure is determined by the permissible stresses, in a cast structure - by casting capabilities. The quick heating of the nozzle boxes reduces the start-up time of a high-temperature steam turbine, which increases its maneuverability.

Claims (1)

A nozzle box for a high-temperature cylinder of a steam turbine, including sections — supply, transition, and a section distributing steam to nozzle segments, characterized in that the box is made of sections welded together, while the supply section is made of pipe, the transition section is made in the form of a cone, passing from the pipe to the oval, and the section that distributes steam to the nozzle segments is made of two rings - the outer and the inner with plugs at the ends.

Images