A turbine inter casing guide centring seal structure

Abstract

The application provides a turbine inter casing guide centering sealing structure, and belongs to the technical field of aero-engine structure design. The turbine inter casing guide centering sealing structure comprises a guide blade, an outer ring, an inner ring, an inner ring fixing ring, a plug cover, a force bearing inner ring casing, a cover plate, a bearing seat and an inner ring centering ring. The upper edge plate of the guide blade is centered with the front hanging point and the rear hanging point of the outer ring by using the outer surface of the front hook and the inner surface of the rear hook. The inner ring is radially pinned to the guide blade. One side of the inner ring fixing ring is fixed to the inner side of the inner ring, and the other side of the inner ring fixing ring is provided with the inner ring centering ring between the force bearing inner ring casing, so as to realize the centering of the whole guide structure. The bearing seat is installed on the inner side of the force bearing inner ring casing, and the plug cover is installed on the bearing seat. One side of the cover plate is installed on the inner ring centering ring through a connecting piece, and the other side of the cover plate is connected with the plug cover on the bearing seat.

Description

Technical Field

[0001] This application belongs to the field of aero-engine design, and specifically relates to a centering and sealing structure for a turbine inter-casing guide. Background Technology

[0002] The turbine interstage casing, located between the high-pressure turbine and the low-pressure turbine, serves as a support casing for the rear support point of the high-pressure turbine and the front support point of the low-pressure turbine. It is one of the engine's main load-bearing components, responsible for load-bearing and rectifying the airflow at the high-pressure turbine outlet. The low-pressure turbine guide vane is located at the rear of the turbine interstage casing, allowing the main combustion gas to flow smoothly through the casing to the front end of the low-pressure turbine, thereby reducing interstage leakage losses.

[0003] like Figure 1 The diagram shows a schematic of the installation structure 10 between the low-pressure turbine guide vane and the turbine casing in the prior art. The upper edge plate of the guide vane 11 is centered by engaging with the outer ring 12 using the outer surface of the front hook and the inner surface of the rear hook. The inner ring 13 is centered with the radial pin of the guide vane 11. Considering assembly requirements, these two engagements are clearance fits. Due to the clearance design and dimensional tolerances, this positioning method may result in extreme runout of the guide vane 11 within the slot of the outer ring 12. When the guide vane 11 itself wobbles, the outer ring 12 serves as a support point, causing the honeycomb on the inner ring 13 and the inner ring fixing ring 14 to become eccentric. This results in the actual eccentricity of the three-layer honeycomb ring of the guide exceeding the maximum eccentricity required by the design, posing a risk of rotor-stator jamming. At the same time, the turbine casing is in a high-temperature environment during operation, and the temperature difference between the plug 15 and the load-bearing inner ring casing 16 is large, resulting in axial and radial deformation inconsistency. The cover plate 17 connected to it bears a high level of thermal stress, and the wobble of the guide vane 11 exacerbates the relative deformation between the two, causing the thermal stress of the cover plate 17 to reach an even higher level, posing a risk of structural failure to the cover plate 17. Summary of the Invention

[0004] The purpose of this application is to provide a centering and sealing structure for a turbine inter-casing guide to solve or mitigate at least one of the problems in the prior art.

[0005] The technical solution of this application is: a centering and sealing structure for a turbine inter-casing guide, comprising: guide vanes, an outer ring, an inner ring, an inner ring fixing ring, a plug, a load-bearing inner ring casing, a cover plate, a bearing seat, and an inner ring centering ring;

[0006] The upper edge plate of the guide vane is centered and engaged with the front and rear hook points of the outer ring by the outer surface of the front hook and the inner surface of the rear hook.

[0007] The inner ring is centered with the radial pin of the guide vane;

[0008] One side of the inner ring fixing ring is fixed to the inner side of the inner ring, and the other side of the inner ring fixing ring is provided with an inner ring centering ring between it and the load-bearing inner ring housing, thereby achieving centering of the entire guide structure.

[0009] The bearing housing is installed on the inner side of the load-bearing inner ring casing, and a plug is installed on the bearing housing;

[0010] One side of the cover plate is mounted on the inner ring centering ring via a connector, and the other side of the cover plate is connected to the plug on the bearing seat.

[0011] In an optional embodiment of this application, the lower edge plate of the guide vane is provided with a rectangular boss that is inserted into the inner ring, and the guide vane and the inner ring are axially positioned by the rectangular boss.

[0012] In an optional embodiment of this application, one side of the cover plate is connected by a connector passing through the inner ring fixing ring, the inner ring centering ring, and the cover plate.

[0013] In an optional embodiment of this application, the cover plate is thinner and has a larger turning angle compared to existing cover plates.

[0014] In an optional embodiment of this application, the cover plate is made of a resilient metal material.

[0015] In an optional embodiment of this application, the inner ring centering ring is provided with an inner stop and an outer stop, and the inner stop and the outer stop are respectively interference-fitted with the inner ring fixing ring and the load-bearing inner ring casing.

[0016] In an optional embodiment of this application, the inner ring and the inner ring fixing ring are provided with honeycomb rings.

[0017] The turbine inter-casing guide centering and sealing structure provided in this application improves the reliability of centering and solves the problem of excessive thermal stress on the cover plate caused by the deformation incoordination between the load-bearing inner ring casing and the plug, which is beneficial to improving the reliability of the turbine structure and the service life of the parts. Attached Figure Description

[0018] To more clearly illustrate the technical solutions provided in this application, the accompanying drawings will be briefly described below. Obviously, the drawings described below are merely some embodiments of this application.

[0019] Figure 1 This is a schematic diagram of the installation structure of the low-pressure turbine guide and the turbine casing in the prior art.

[0020] Figure 2 This is a schematic diagram of the centering and sealing structure of the turbine stage inter-casing guide in this application.

[0021] Figure 3 This is a schematic diagram showing the gap between the upper and lower mounting planes of the inner ring centering ring in this application.

[0022] Figure label:

[0023] 20-Turbine stage inter-casing guide centering seal structure

[0024] 21-Guide Blade

[0025] 22-Outer Ring

[0026] 23-Inner Ring

[0027] 24-Inner Ring Fixing Ring

[0028] 25-Plug

[0029] 26-Bearing Inner Ring Casing

[0030] 27-Cover plate

[0031] 28-Bearing Housing

[0032] 29-Inner Ring Centering Ring Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings.

[0034] To enhance the structural stability of the turbine inter-casing guide, reduce the thermal stress of the cover plate, improve the service life of turbine components, and solve the honeycomb eccentricity problem of the inner ring and inner ring fixing ring caused by the yaw of the guide blades, as well as the high thermal stress problem of the cover plate caused by the deformation incoordination between the plug and the load-bearing inner ring casing, this application provides a centering and sealing structure for the turbine inter-casing guide.

[0035] like Figure 2 As shown, the turbine stage inter-casing guide centering and sealing structure 20 provided in this application includes: guide vane 21, outer ring 22, inner ring 23, inner ring fixing ring 24, plug 25, load-bearing inner ring casing 26, cover plate 27, bearing seat 28 and inner ring centering ring 29.

[0036] The outer ring 22 is fixed to the turbine casing by a connector. Its inner front end and rear end are provided with a front hook and a rear hook extending backward (in the direction of airflow). The upper edge plate of the guide vane 21 is provided with a front hook and a rear hook respectively. The upper edge plate of the guide vane 21 is centered and matched with the front hook and the rear hook of the outer ring 22 by the outer surface of the front hook and the inner surface of the rear hook.

[0037] The inner ring 23 and the guide vane 21 are radially centered. In one embodiment of this application, a rectangular boss 211 is provided on the front side of the lower edge plate of the guide vane 21, which is inserted into the inner ring 23. The axial positioning of the guide vane 21 and the inner ring 23 is achieved by the rectangular boss 211.

[0038] The outer side of the inner ring fixing ring 24 is fixed to the inner side of the inner ring 23 by a connector. An inner ring centering ring 29 is provided between the inner side of the inner ring fixing ring 24 and the load-bearing inner ring housing 26. Its two ends are respectively assembled on the inner ring fixing ring 24 and the load-bearing inner ring housing 26 to achieve centering of the entire guide structure.

[0039] The bearing housing 28 is installed inside the load-bearing inner ring casing 26, and a plug 25 is installed on it.

[0040] One side of the cover plate 27 is mounted on the inner ring centering ring 29 via a connector, and the other side of the cover plate 27 is connected to the plug 25 on the bearing housing 28. The upper side of the cover plate 27 is connected to the inner ring fixing ring 24, the inner ring centering ring 29, and the cover plate 27 via a connecting bolt. The cover plate 27 separates the upper cavity A of the load-bearing inner ring housing 26 and the cavities B and C enclosed by the bearing housing 28. In a preferred embodiment of this application, the cover plate 27 has a thinner thickness and a larger angle to increase its flexibility, while eliminating the bolt connection between the cover plate 27 and the mounting edge of the load-bearing inner ring housing 26, thereby effectively reducing excessive thermal stress on the cover plate 27 caused by the deformation mismatch between the load-bearing inner ring housing 26 and the plug 25. Furthermore, the cover plate 27 can be made of an elastic metal material to further improve its flexibility.

[0041] In this application, the load-bearing inner ring casing 26 is configured as a structure that is thicker and stronger than the upper part of the cover plate 17 in the prior art.

[0042] like Figure 3 As shown, the inner ring centering ring 29 of this application is provided with an inner stop 291 and an outer stop 292. The two stops are respectively interference-fitted with the structural end faces of the inner ring fixing ring 24 and the load-bearing inner ring housing 26. During installation, the inner ring centering ring 29 is first inserted by interference fit, and then connected and positioned with the inner ring fixing ring 24 and the load-bearing inner ring housing 26 by bolts. Finally, the cover plate 27 is assembled to realize the centering function of the guide.

[0043] In some embodiments of this application, the inner ring 23 and the inner ring fixing ring 24 are provided with honeycomb rings for sealing.

[0044] In the turbine inter-casing guide centering and sealing structure provided in this application, the inner and outer stops of the inner ring centering ring 29 are interference-fitted with the inner ring fixing ring 24 and the load-bearing inner ring casing 26, thereby centering the inner ring 23 and the three honeycomb rings on the inner ring fixing ring 24 with the load-bearing inner ring casing 26 inside the turbine inter-casing, and fixing them with connecting bolts. This application changes the original radial pin centering structure of the guide vane to stop centering, improving the reliability of centering; at the same time, the cover plate 27 is optimized with a flexible structure and connected to the mounting edge of the inner ring fixing ring 24, solving the problem of excessive thermal stress on the cover plate 27 caused by the deformation incoordination between the load-bearing inner ring casing 26 and the plug 25, which is beneficial to improving the reliability of the turbine structure and the service life of the parts.

[0045] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A turbine inter- casing guide centering seal structure, characterized by, Comprise: Guide vane, outer ring, inner ring, inner ring fixing ring, plug cover, force bearing inner ring machine case, cover plate, bearing seat and inner ring centering ring; The upper edge plate of the guide vane is centered with the front hook outer surface and the rear hook inner surface and the front hanging point and the rear hanging point of the outer ring; The inner ring is centered with the guide vane radial pin shaft; One side of the inner ring fixing ring is fixed on the inner side of the inner ring, and the other side of the inner ring fixing ring is provided with the inner ring centering ring between the force bearing inner ring machine case, so as to realize the centering of the whole guide structure; The inner ring centering ring is provided with inner and outer stop openings, which are respectively interference fitted with the inner ring fixing ring and the force bearing inner ring machine case; The inner ring and the inner ring fixing ring are provided with honeycomb rings; The bearing seat is installed on the inner side of the force bearing inner ring machine case, and the plug cover is installed on the bearing seat; One side of the cover plate is installed on the inner ring centering ring through a connecting piece, and the other side of the cover plate is connected with the plug cover on the bearing seat.

2. The turbine inter- casing guide centering seal structure of claim 1, wherein The lower edge plate of the guide vane is provided with a rectangular boss inserted into the inner ring, and the axial positioning of the guide vane and the inner ring is realized through the rectangular boss.

3. The turbine inter- casing guide centering seal structure of claim 1, wherein One side of the cover plate is connected through a connecting piece passing through the inner ring fixing ring, the inner ring centering ring and the cover plate.

4. The interturbine casing guide centering seal structure of claim 3, wherein The cover plate is made of elastic metal material.

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