Two-stage low-pressure turbine disc shaft connecting structure

Abstract

The invention provides a two-stage low-pressure turbine disc shaft connecting structure, and belongs to the technical field of gas turbines. A high-pressure turbine rear shaft; a labyrinth ring; the adapter shaft is mounted on the low-pressure turbine shaft and comprises a first axial part and a second axial part which are connected with a low-pressure turbine shaft sleeve tooth structure, the first axial part and the second axial part are connected through a radial part, and a radial plate is arranged on the second axial part; the two-stage low-pressure turbine disc comprises a first-stage low-pressure turbine disc and a second-stage low-pressure turbine disc, and the first-stage low-pressure turbine disc and the second-stage low-pressure turbine disc are connected to a radial plate of the adapter shaft through a self-limiting double-end connecting piece; wherein a rear bearing inner ring assembly surface is arranged on the outer side of the rear end of the first axial part, a rear bearing is mounted on the assembly surface, a front bearing outer ring is arranged on the inner side of the second axial part, and the front bearing is matched with the front bearing outer ring to support a rear shaft of the high-pressure turbine; a sealing honeycomb and an oil sealing coating which are matched with the labyrinth ring are arranged at the front end of the second axial part, so that the sealing honeycomb and the oil sealing coating form a front bearing oil cavity oil sealing structure together with the labyrinth ring.

Description

Technical Field

[0001] The present application belongs to the technical field of aero-engines and gas turbines, and in particular relates to a two-stage low-pressure turbine disk-shaft connection structure. Background Art

[0002] like Figure 1 The figure shows a typical two-stage low-pressure turbine disk-shaft connection structure in modern aircraft engines and gas turbines. In the typical two-stage low-pressure turbine disk-shaft connection structure 100, a low-pressure turbine shaft 110 with a spoke 111 is usually used to connect with the first-stage low-pressure turbine disk 121 and the second-stage low-pressure turbine disk 121 in the two-stage turbine disk. However, in this structural layout, the front bearing 130 and its lubricating oil sealing system and the high-pressure turbine rear journal 140 require a large structural space, which leads to a large axial space between the high-pressure and low-pressure turbines, increases the engine length, and greatly increases the engine weight. In addition, due to the limitation of the structural space, the connection position of the spoke 111 of the low-pressure turbine shaft 110 and the low-pressure turbine disk is relatively high, and the stress at the position of the spoke 111 is relatively high. At the same time, the bolt assembly is difficult, and there is a situation where the same bolt connects 4 rotor parts on the spoke 111, which is relatively poor in safety. Summary of the invention

[0003] The object of the present application is to provide a two-stage low-pressure turbine disk-shaft connection structure to solve or alleviate at least one problem in the background technology.

[0004] The technical solution of the present application is: a two-stage low-pressure turbine disk-shaft connection structure, comprising:

[0005] Low-pressure turbine shaft;

[0006] High-pressure turbine rear axle;

[0007] Comb tooth ring;

[0008] An adapter shaft mounted on the low-pressure turbine shaft, the adapter shaft comprising a first axial portion connected to the low-pressure turbine shaft sleeve gear structure and a second axial portion parallel to the first axial portion, the first axial portion and the second axial portion are connected via a radial portion, and a spoke plate is provided on the second axial portion;

[0009] A two-stage low-pressure turbine disk, wherein the two-stage low-pressure turbine disk comprises a first-stage low-pressure turbine disk and a second-stage low-pressure turbine disk, wherein the first-stage low-pressure turbine disk and the second-stage low-pressure turbine disk are connected to the spoke plate of the adapter shaft through a self-limiting double-head connector;

[0010] A rear bearing inner ring assembly surface is provided on the outer side of the rear end of the first axial portion, and the rear bearing is mounted on the rear bearing inner ring assembly surface; a front bearing outer ring is provided on the inner side of the second axial portion, and the front bearing and the front bearing outer ring cooperate to support the high-pressure turbine rear shaft;

[0011] The outer surface of the second axial portion forms a graphite oil sealing surface, and the front end of the second axial portion is provided with a sealing honeycomb and an oil sealing coating adapted to the grate ring, thereby forming a front bearing oil cavity oil sealing structure together with the grate ring.

[0012] In a preferred embodiment of the present application, a front positioning surface and a rear positioning surface are respectively provided on the front and rear sides of the first axial portion of the adapter shaft, and a front and rear double stop positioning structure is formed by the front positioning surface and the rear positioning surface to ensure the connection and positioning of the adapter shaft and the low-pressure turbine shaft.

[0013] In a preferred embodiment of the present application, an adjustment pad is provided between the adapter shaft and the low-pressure turbine shaft, and the axial position of the adapter shaft and the two-stage low-pressure turbine disk is adjusted and controlled by the adjustment pad.

[0014] In a preferred embodiment of the present application, a special-shaped section with a rectangular cross-section is provided in the middle of the self-limiting double-head connector, and threaded sections are provided on both sides of the special-shaped section. The connection between the first-stage low-pressure turbine disc, the second-stage low-pressure turbine disc and the spoke plate of the adapter shaft is achieved by means of locking nuts installed on the threaded sections.

[0015] In a preferred embodiment of the present application, the first-stage low-pressure turbine disc and the second-stage low-pressure turbine disc respectively have a first-stage mounting edge extending forward and a second-stage mounting edge extending backward, bolt holes are provided on the first-stage mounting edge and the second-stage mounting edge extending backward, and any of the mounting edges is provided with a special hole adapted to fit the self-limiting double-head connecting piece.

[0016] In a preferred embodiment of the present application, a boss is provided on the outer side of the sealing honeycomb on the second axial portion, and the boss overlaps with the center of the first-stage low-pressure turbine disk.

[0017] In a preferred embodiment of the present application, a first vent hole is provided at the front end of the second axial portion, and a second vent hole is provided on the spoke plate, so that the front bearing oil chamber sealing structure is connected to the rear bearing oil chamber through the first vent hole and the second vent hole.

[0018] In a preferred embodiment of the present application, an oil return hole is provided on the radial portion for connecting the front bearing oil chamber and the rear bearing oil chamber.

[0019] In a preferred embodiment of the present application, the web is axially adapted to the front bearing outer ring.

[0020] In a preferred embodiment of the present application, sealing grate teeth are provided outside the spoke plate, and the sealing grate teeth and the honeycomb ring installed on the load-bearing casing form a sealing structure to separate the chamber between the first-stage low-pressure turbine disc and the second-stage low-pressure turbine disc.

[0021] The two-stage low-pressure turbine disk-shaft connection structure provided by the present application has the following advantages:

[0022] 1) It can shorten the axial distance between the low-pressure turbine disk and the high-pressure turbine disk, effectively shorten the axial length of the engine, reduce the engine weight, and solve the problem of too long assembly space between the front bearing and its lubricating oil sealing system and the rear journal of the high-pressure turbine disk.

[0023] 2) The integrated adapter shaft integrates multiple functions such as sealing, lubrication, and force transmission, and eliminates the structure of multiple rotor parts (4 or more) fastened by bolts, which improves the reliability and safety of the rotor and reduces the difficulty of assembly. It can reduce a row of bolt structures, reduce the radial height of the turbine disk connecting spokes and connecting bolts, reduce the stress at this position, simplify the bearing outer ring support structure and the outer layer structure of the lubricating oil cavity, make the bearing lubricating oil cavity structure more compact, reduce the radial height limit of the turbine disk center, effectively improve the strength reserve of the turbine disk, and provide an option for the design of high-load turbine disks;

[0024] 3) The spoke plate of the low-pressure turbine shaft has been cancelled to improve the processing performance of the low-pressure turbine shaft. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solution provided by the present application, the following is a brief introduction to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present application.

[0026] Figure 1 This is a schematic diagram of a typical two-stage low-pressure turbine disk-shaft connection structure.

[0027] Figure 2 This is a schematic diagram of the two-stage low-pressure turbine disk-shaft connection structure of the present application.

[0028] Figure 3 This is a schematic diagram of the structure of the first-stage low-pressure turbine disk in this application.

[0029] Figure 4 This is a schematic diagram of the structure of the second-stage low-pressure turbine disc in this application.

[0030] Figure 5 This is a schematic diagram of the transfer shaft in this application.

[0031] Figure 6 This is a schematic diagram of the self-limiting double-head connector in this application.

[0032] Figure 7 Schematic diagram of the adjustment pad in this application.

[0033] Reference numerals:

[0034] 200-Two-stage low-pressure turbine disc connection structure

[0035] 210-Low-pressure turbine shaft

[0036] 220-two-stage low-pressure turbine disc, 221-first-stage low-pressure turbine disc, 222-second-stage low-pressure turbine disc 230-adapter shaft

[0037] 231 - first axial portion,

[0038] 2311-Torque transmission gear

[0039] 2312-Front positioning surface

[0040] 2313-Rear positioning surface

[0041] 2314-Rear bearing inner ring assembly surface

[0042] 232- Second axial portion

[0043] 2321-Graphite oil seal surface

[0044] 2322-Front bearing outer ring

[0045] 2323-Oil sealing coating

[0046] 2324-Seal the Hive

[0047] 2325-First vent

[0048] 233-Radial part

[0049] 2331-Oil return hole

[0050] 234-Spoke Plate

[0051] 2341-Special-shaped through hole

[0052] 2342-Seal the comb teeth

[0053] 2343-Second vent

[0054] 240-High-pressure turbine rear axle

[0055] 251-front bearing, 252-rear bearing

[0056] 260-bearing seat,

[0057] 261-first clamping nut, 262-second clamping nut, 263-third clamping nut

[0058] 270-Self-limiting double-head connector

[0059] 271-Special-shaped segment

[0060] 272-thread segment

[0061] 273-lock nut

[0062] 280-comb tooth ring

[0063] 290-Adjustment pad DETAILED DESCRIPTION

[0064] In order to make the purpose, technical solutions and advantages of the implementation of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below in conjunction with the drawings in the embodiments of this application.

[0065] In order to overcome the problems in the prior art, the present application provides a novel two-stage low-pressure turbine disk-shaft connection structure.

[0066] like Figures 2 to 7 As shown, the two-stage low-pressure turbine disk connection structure 200 of the present application includes: a low-pressure turbine shaft 210, a two-stage low-pressure turbine disk 220, a transfer shaft 230, a high-pressure turbine rear shaft 240, a front bearing 251 and a rear bearing 252, a bearing seat 260, a plurality of clamping nuts (including a first clamping nut 261, a second clamping nut 262 and a third clamping nut 263), a self-limiting double-headed connector 270 and a comb ring 280.

[0067] The two-stage low-pressure turbine disk 220 includes a first-stage low-pressure turbine disk 221 and a second-stage low-pressure turbine disk 222. Figure 3 and Figure 4 As shown, the first-stage low-pressure turbine disc 221 is provided with a rearward first-stage mounting edge 2111, and the second-stage low-pressure turbine disc 222 is provided with a forward second-stage mounting edge 2121. Bolt holes are provided on both the first-stage mounting edge 2111 and the second-stage mounting edge, and a special-shaped hole 2112 is provided at the rear section of the bolt hole of the first-stage mounting edge 2111, which is used to form a self-limiting connection with the special-shaped section 271 in the middle of the self-limiting double-headed connector 270, so as to realize the axial limitation and circumferential anti-rotation of the self-limiting double-headed connector 270. It is understandable that the special-shaped hole 2112 can also be provided on the second-stage mounting edge 2121.

[0068] The adapter shaft 230 is mounted on the low-pressure turbine shaft 210 and can rotate together with the low-pressure turbine shaft 210. Figure 5 As shown, the adapter shaft 230 has a first axial portion 231 and a second axial portion 232 substantially parallel thereto. The first axial portion 231 and the second axial portion 232 are connected via a radial portion 233 , and a spoke plate 234 extending radially outward is disposed on the second axial portion 232 .

[0069] A torque transmission sleeve tooth 2311 is provided on the inner side of the first axial portion 231, and the adapter shaft 230 is connected to the low-pressure turbine shaft 210 through the torque transmission sleeve tooth 2311 and is locked through the third clamping nut 263 to achieve torque transmission between the adapter shaft 230 and the low-pressure turbine shaft 210. A front positioning surface 2312 and a rear positioning surface 2313 are provided on the front and rear sides of the torque transmission sleeve tooth 2311 of the first axial portion 231, respectively, and a front and rear double stop positioning structure is formed by the front positioning surface 2312 and the rear positioning surface 2313 to ensure the positioning reliability of the adapter shaft 230 and the low-pressure turbine shaft 210, and to limit the harmful deformation of the adapter shaft 230 under the engine maneuvering load. A rear bearing inner ring assembly surface 2314 is provided on the outer side of the rear end of the first axial portion 231, and the rear bearing 252 is installed on the rear bearing inner ring assembly surface 2314. The bearing seat 260 is supported on the rear bearing 252 and locked by a second clamping nut 262, so as to transfer the rotor load to the rear bearing structure of the engine.

[0070] The outer surface of the second axial portion 232 forms a graphite oil sealing surface 2321, which cooperates with the graphite ring to form a rear bearing oil chamber oil sealing structure to ensure that the lubricating oil does not leak during operation. The front bearing outer ring 2322 is formed in the inner middle part of the second axial portion 232. The front bearing 251 is installed at the front bearing outer ring 2322 and is locked by the first clamping nut 261 to support the high-pressure turbine rear shaft 240. The front end of the second axial portion 232 is provided with a sealing honeycomb 2324, an oil sealing coating 2323 and a first vent hole 2325, which together with the comb ring 280 form a front bearing oil chamber oil sealing structure to ensure that the lubricating oil does not leak during operation. In the present application, a boss is provided on the outer side of the sealing honeycomb 2324, which overlaps with the center of the first-stage low-pressure turbine disk 221, so as to ensure that the sealing honeycomb 2324 and the oil sealing coating 2323 do not undergo significant harmful deformation during operation.

[0071] An oil return hole 2331 is provided on the radial portion 233 inside the graphite oil seal ring 2321 to connect the front bearing oil chamber and the rear bearing oil chamber.

[0072] The spoke plate 234 is roughly located outside the front bearing outer ring 2322 of the second axial portion 232. The spoke plate 234 forms a mounting edge for connecting the first-stage low-pressure turbine disk 221 and the second-stage low-pressure turbine disk 222. A special-shaped through hole 2341 is provided on the spoke plate 234 for assembling the self-limiting double-head connector 270 and fastening the two-stage low-pressure turbine disk 220 through a nut. Among them, a sealing grate 2342 is provided outside the spoke plate 234, which can form a sealing structure with the honeycomb ring installed on the load-bearing casing (not shown) to separate the chambers between the first and second low-pressure turbine disks. Furthermore, a second vent 2343 is also provided on the spoke plate 234, which connects the front bearing oil chamber and the rear bearing oil chamber.

[0073] like Figure 6As shown in the schematic diagram of the self-limiting double-headed connector, the middle section of the self-limiting double-headed connector 270 is set as a special-shaped section 271, whose cross section is a rectangular rounded corner, which can form a self-limiting structure with the special-shaped through hole 2341 on the spoke plate of the adapter shaft 230 to ensure the front and rear fastening of the self-limiting double-headed connector 270. The two sides of the special-shaped section 271 are threaded sections 272, and the threaded sections 272 are installed with locking nuts 273, so as to fix the first-stage low-pressure turbine disk 221, the spoke plate 234 of the adapter shaft 230 and the second-stage low-pressure turbine disk 222 together.

[0074] like Figure 7 As shown, the present application also includes an adjustment pad 290, which is arranged between the rear positioning structure of the low-pressure turbine shaft 210 and the adapter shaft 230, and a grindable surface 291 is arranged on the side facing the adapter shaft 230, which is used to adjust and control the axial position of the adapter shaft 230 and the two-stage low-pressure turbine disk 220.

[0075] The two-stage low-pressure turbine disk-shaft connection structure provided by the present application has the following advantages:

[0076] 1) It can shorten the axial distance between the low-pressure turbine disk and the high-pressure turbine disk, effectively shorten the axial length of the engine, reduce the engine weight, and solve the problem of too long assembly space between the front bearing and its lubricating oil sealing system and the rear journal of the high-pressure turbine disk.

[0077] 2) The integrated adapter shaft integrates multiple functions such as sealing, lubrication, and force transmission, and eliminates the structure of multiple rotor parts (4 or more) fastened by bolts, which improves the reliability and safety of the rotor and reduces the difficulty of assembly. It can reduce a row of bolt structures, reduce the radial height of the turbine disk connecting spokes and connecting bolts, reduce the stress at this position, simplify the bearing outer ring support structure and the outer layer structure of the lubricating oil cavity, make the bearing lubricating oil cavity structure more compact, reduce the radial height limit of the turbine disk center, effectively improve the strength reserve of the turbine disk, and provide an option for the design of high-load turbine disks;

[0078] 3) The spoke plate of the low-pressure turbine shaft has been cancelled to improve the processing performance of the low-pressure turbine shaft.

[0079] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A two-stage low-pressure turbine disk-shaft connection structure, characterized in that: include: Low-pressure turbine shaft; High-pressure turbine rear axle; Comb tooth ring; An adapter shaft mounted on the low-pressure turbine shaft, the adapter shaft comprising a first axial portion connected to the low-pressure turbine shaft sleeve gear structure and a second axial portion parallel to the first axial portion, the first axial portion and the second axial portion are connected via a radial portion, and a spoke plate is provided on the second axial portion; A two-stage low-pressure turbine disk, wherein the two-stage low-pressure turbine disk comprises a first-stage low-pressure turbine disk and a second-stage low-pressure turbine disk, wherein the first-stage low-pressure turbine disk and the second-stage low-pressure turbine disk are connected to the spoke plate of the adapter shaft through a self-limiting double-head connector; A rear bearing inner ring assembly surface is provided on the outer side of the rear end of the first axial portion, and the rear bearing is mounted on the rear bearing inner ring assembly surface; a front bearing outer ring is provided on the inner side of the second axial portion, and the front bearing and the front bearing outer ring cooperate to support the high-pressure turbine rear shaft; The outer surface of the second axial portion forms a graphite oil sealing surface, and the front end of the second axial portion is provided with a sealing honeycomb and an oil sealing coating adapted to the grate ring, thereby forming a front bearing oil cavity oil sealing structure together with the grate ring.

2. The two-stage low-pressure turbine disk-shaft connection structure according to claim 1, characterized in that: The front and rear sides of the first axial portion of the adapter shaft are respectively provided with a front positioning surface and a rear positioning surface, and the front and rear positioning surfaces form a front and rear double stop positioning structure to ensure the connection and positioning of the adapter shaft and the low-pressure turbine shaft.

3. The two-stage low-pressure turbine disk-shaft connection structure according to claim 3, characterized in that: An adjustment pad is provided between the adapter shaft and the low-pressure turbine shaft, and the axial position of the adapter shaft and the two-stage low-pressure turbine disk is adjusted and controlled by the adjustment pad.

4. The two-stage low-pressure turbine disk-shaft connection structure according to claim 1, characterized in that: The middle part of the self-limiting double-head connector is provided with a special-shaped section with a rectangular cross-section, and threaded sections are provided on both sides of the special-shaped section. The connection between the first-stage low-pressure turbine disc, the second-stage low-pressure turbine disc and the spoke plate of the adapter shaft is achieved by installing a locking nut on the threaded section.

5. The two-stage low-pressure turbine disk-shaft connection structure according to claim 4, characterized in that: The first-stage low-pressure turbine disc and the second-stage low-pressure turbine disc respectively have a first-stage mounting edge extending forward and a second-stage mounting edge extending backward, and bolt holes are provided on the first-stage mounting edge and the second-stage mounting edge extending backward, and any mounting edge is provided with a special-sex hole adapted to the self-limiting double-head connecting piece.

6. The two-stage low-pressure turbine disk-shaft connection structure according to claim 1, characterized in that: A boss is arranged on the outer side of the sealing honeycomb on the second axial portion, and the boss is overlapped with the center of the first-stage low-pressure turbine disk.

7. The two-stage low-pressure turbine disk-shaft connection structure according to claim 1, characterized in that: A first vent hole is disposed at the front end of the second axial portion, and a second vent hole is disposed on the spoke plate. The front bearing oil chamber sealing structure is connected to the rear bearing oil chamber through the first vent hole and the second vent hole.

8. The two-stage low-pressure turbine disk-shaft connection structure according to claim 1, characterized in that: The radial portion is provided with an oil return hole for connecting the front bearing oil chamber and the rear bearing oil chamber.

9. The two-stage low-pressure turbine disk-shaft connection structure according to claim 1, characterized in that: The web is axially matched with the front bearing outer ring.

10. The two-stage low-pressure turbine disk-shaft connection structure according to claim 9, characterized in that: The spoke plate is provided with sealing grate teeth outside, and the sealing grate teeth and the honeycomb ring installed on the load-bearing casing form a sealing structure to separate the chamber between the first-stage low-pressure turbine disk and the second-stage low-pressure turbine disk.

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