A self-locking structure for a low-pressure rotor of a gas turbine

Abstract

The present invention belongs to the technical field of gas turbine low-pressure rotor connection structure, and specifically relates to a self-locking structure of a gas turbine low-pressure rotor, including a nut locking member and a turbine shaft locking member; the turbine shaft locking member is in a circular ring shape; the nut locking member is arranged on the inner side of the turbine shaft locking member, and can slide between an unlocking position or a locking position; when the nut locking member is in the unlocking position, the tightening nut can rotate relative to the turbine shaft locking member, so that the tightening nut can be screwed to the front end of the turbine shaft; when the nut locking member is in a locked state, the nut locking member can cooperate with the tightening nut and the turbine shaft locking member spline at the same time. In this scheme, the turbine shaft and the tightening nut can be locked. Since the self-locking structure in this scheme is not connected to the compressor rear shaft neck key, it is not necessary to have a high coaxiality with the compressor rear shaft neck when performing the locking action, thereby reducing the installation difficulty of the self-locking structure.

Description

Technical Field

[0001] The invention belongs to the technical field of gas turbine low-pressure rotor connection structures, and in particular relates to a self-locking structure of a gas turbine low-pressure rotor. Background Art

[0002] Gas turbine rotors are generally divided into high-pressure rotors and low-pressure rotors. The low-pressure rotor is composed of a low-pressure compressor rotor and a low-pressure turbine rotor. After the two rotors are assembled separately, they are fixed together through a connecting device. However, due to the long axial dimension of the rotor system, especially the low-pressure turbine rotor, a long hollow shaft is required to pass through the combustion chamber and connect with the low-pressure compressor rotor; the location of the connecting device is limited and narrow, and is generally located in the inner hole of the shaft end; during assembly, the connecting device can only be finally tightened and locked after the rest of the gas turbine structure is assembled in place, but at this time, the locking assembly tool has problems such as inaccessible space, extremely large assembly torque, and difficult tooling design; the connection device must be able to self-position and lock, etc., which will cause general connection devices or structures (such as flange couplings, shaft end nuts, arc end teeth, claws, etc.) to fail to meet the requirements.

[0003] The prior art discloses a locking connection device for a low-pressure rotor of a gas turbine, with publication number CN114687861A. The solution utilizes a locking bushing structure, which can automatically lock in a narrow assembly space and achieve reliable connection of the turbine shaft.

[0004] However, this solution has the following problems in actual use: since this technology requires the locking bushing key to be connected to the compressor rear shaft neck in order to achieve locking, and there is often a problem of misalignment between the compressor rear shaft neck and the low-pressure turbine shaft, it increases the difficulty of locking the locking bushing and the compressor rear shaft neck. Sometimes, the position of the compressor rear shaft neck or the turbine shaft needs to be repeatedly adjusted to make the distance between the two axes meet the locking requirements.

[0005] Therefore, it is necessary to design a self-locking structure that can lock the connection position between the compressor rear journal and the turbine shaft without calibrating the axis of the two. Summary of the invention

[0006] In order to solve the above problems existing in the prior art, the present invention provides a self-locking structure for a low-pressure rotor of a gas turbine.

[0007] The technical solution adopted by the present invention is:

[0008] A self-locking structure for a low-pressure rotor of a gas turbine, comprising a nut locking member and a turbine shaft locking member;

[0009] The low-pressure rotor comprises a compressor rotor and a turbine rotor, the rear end of the compressor rotor has a compressor rear journal, and the turbine rotor has a turbine shaft; the compressor rear journal and the front end of the turbine shaft can be sleeve-connected, and the front end of the turbine shaft is threadedly connected with a tightening nut, and the tightening nut fixes the relative position of the compressor rear journal and the turbine shaft;

[0010] The turbine shaft locking piece is in a circular shape and is fixed to the front end of the turbine shaft; the nut locking piece is arranged on the inner side of the turbine shaft locking piece and can slide relative to the axial direction of the turbine shaft locking piece so that the nut locking piece is placed in an unlocking position or a locking position; when the nut locking piece is in the unlocking position, the tightening nut can be rotated relative to the turbine shaft locking piece so that the tightening nut can be tightened to the front end of the turbine shaft; when the nut locking piece is in a locked state, the nut locking piece can simultaneously cooperate with the tightening nut and the turbine shaft locking piece spline.

[0011] As an alternative or supplement to the above self-locking structure: the outer diameter of the turbine shaft locking piece is not larger than the outer diameter of the front end of the turbine shaft, so that the turbine shaft locking piece can be withdrawn from the rear journal of the compressor along with the turbine shaft.

[0012] As an alternative or supplement to the above self-locking structure: the outer diameter of the nut locking piece is not larger than the outer diameter of the front end of the turbine shaft, so that the nut locking piece can be withdrawn from the rear journal of the compressor along with the turbine shaft.

[0013] As an alternative or supplement to the above self-locking structure: a turbine shaft locking spline is arranged on the outer side of the front end of the turbine shaft locking member, and a shaft end spline tooth is arranged on the front end of the turbine shaft, and the turbine shaft locking spline and the shaft end spline tooth are key-connected to each other.

[0014] As an alternative or supplement to the above-mentioned self-locking structure: a nut cone surface is provided on the outer side of the rear end of the tightening nut, and a journal cone surface is provided on the inner side of the compressor rear journal; the nut cone surface can fit with the journal cone surface to adjust the axis of the compressor rear journal when the tightening nut is tightened.

[0015] As an alternative or supplement to the above-mentioned self-locking structure: a nut locking spline is arranged on the outer side of the front end of the nut locking piece; an inner locking spline is arranged on the inner side of the front end of the turbine shaft locking piece; a nut second spline is arranged on the inner side of the front end of the tightening nut; when the nut locking piece is in the locking position, the front end of the nut locking spline is connected to the second nut spline, and the rear end is connected to the inner locking spline.

[0016] As an alternative or supplement to the above-mentioned self-locking structure: a compression spring is arranged between the turbine shaft locking piece and the nut locking piece, the front end of the nut locking piece is arranged with an outward turning edge, and the rear end of the turbine shaft locking piece is arranged with an inward turning edge, the front end of the compression spring abuts against the outward turning edge, and the rear end abuts against the inward turning edge.

[0017] As an alternative or supplement to the above-mentioned self-locking structure: the rear end of the nut locking member is fixedly connected to a ring-shaped stopper by a pin, and the ring-shaped stopper can abut against the rear end of the turbine shaft locking member to limit the relative sliding position of the nut locking member and the turbine shaft locking member.

[0018] The beneficial effects of the present invention are as follows: the nut locking member and the turbine shaft locking member in the present scheme cooperate with each other and can be key-connected with the turbine shaft and the tightening nut to achieve locking. Since the self-locking structure in the present scheme is not key-connected with the compressor rear shaft neck, when performing the locking action, it is not necessary to have a high coaxiality with the compressor rear shaft neck, thereby reducing the installation difficulty of the self-locking structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below.

[0020] Figure 1 It is a usage state diagram of the self-locking structure of the low-pressure rotor of the gas turbine in this scheme;

[0021] Figure 2 It is a diagram of the matching structure of the tension nut, self-locking structure, and turbine shaft;

[0022] Figure 3 It is a cross-sectional structural diagram of the self-locking structure;

[0023] Figure 4 This is a diagram of the connection status between the compressor rotor and the turbine rotor.

[0024] In the figure: 1-tension nut; 11-first spline of nut; 12-second spline of nut; 13-internal threaded portion; 14-conical surface of nut; 2-nut locking piece; 21-nut locking spline; 22-outward edge; 3-compression spring; 4-pin; 5-annular stopper; 6-turbine shaft locking piece; 61-inner locking spline; 62-turbine shaft locking spline; 63-inward edge; 7-turbine shaft; 71-turbine shaft outer spline; 72-shaft end spline teeth; 8-compressor rear journal; 81-journal cone; 82-journal inner spline; 9-compressor rotor; 10-turbine rotor. DETAILED DESCRIPTION

[0025] The technical solution in this embodiment will be clearly and completely described below in conjunction with the accompanying drawings. The described embodiments are only some of the embodiments, not all of them. Based on the embodiments in this solution, all other embodiments obtained by ordinary technicians in this field without making creative work are within the protection scope of this solution.

[0026] The low-pressure rotor includes two parts: a compressor rotor 9 and a turbine rotor 10; wherein the rear end of the compressor rotor 9 has a compressor rear journal 8, and the turbine rotor 10 has a turbine shaft 7. In the prior art with publication number CN114687861A, a locking connection device for a low-pressure rotor of a gas turbine is disclosed, and the locking connection device is installed at Figure 4 At position A in the middle, a reliable connection between the compressor rotor 9 and the turbine rotor 10 is achieved.

[0027] Example 1

[0028] like Figures 1 to 3 As shown, this embodiment designs a self-locking structure for the low-pressure rotor of a gas turbine, which is also installed on Figure 4 At position A in the embodiment, the self-locking structure can be used as a replacement for the locking connection device of the prior art (CN114687861A). In this embodiment, after the compressor rotor 9 and the turbine rotor 10 are connected and locked by the tightening nut 1, the self-locking structure can cooperate with the spline between the tightening nut 1 and the turbine rotor 10 to achieve locking of the relative position of the tightening nut 1 and the turbine rotor 10.

[0029] The low-pressure rotor in this embodiment includes two parts, namely, a compressor rotor 9 and a turbine rotor 10; wherein, the rear end of the compressor rotor 9 has a compressor rear journal 8, and the turbine rotor 10 has a turbine shaft 7, wherein the compressor rear journal 8 includes a pipe sleeve portion and a cone disk portion connected as one; the pipe sleeve portion is tubular and used for sleeve connection with the turbine shaft 7; the cone disk portion is cone disk-shaped and used for connecting the impeller of the compressor rotor 9; a through hole can be provided on the cone disk portion for air circulation. The front end of the pipe sleeve portion has a journal conical surface 81; when the tightening nut 1 is threadedly connected to the front end of the turbine shaft 7, the rear end of the tightening nut 1 can be pressed against the journal conical surface 81, thereby achieving the effect of tightening the turbine shaft 7 axially forward. The front end of the turbine shaft 7 can be fixed by the tightening nut 1.

[0030] In order to ensure the transmission of force between the compressor rotor 9 and the turbine rotor 10 in the direction of rotation, a turbine shaft outer spline 71 is provided on the outer side wall of the front part of the turbine shaft 7, and a journal inner spline 82 is provided on the inner wall of the pipe sleeve of the compressor rear journal 8. When the turbine shaft 7 is inserted into the pipe sleeve, the turbine shaft outer spline 71 and the journal inner spline 82 are connected to each other (i.e., the turbine shaft outer spline 71 and the journal inner spline 82 are engaged with the keyway). Since there is often a gap at the connection between the turbine shaft 7 and the compressor rear journal 8, it is generally difficult to achieve the coincidence of the axis of the turbine shaft 7 and the axis of the compressor rear journal 8 after the two are assembled. It is very difficult to connect the self-locking structure to the compressor rear journal 8 by key after it is connected to the turbine shaft 7.

[0031] The tensioning nut 1 can be divided into a front section and a rear section along its axial direction; a first internal spline of the nut and a second internal spline of the nut are arranged on the inner side of the front section of the tensioning nut 1, and when a special tool with an external spline is inserted from the center of the front end of the compressor rotor 9, the special tool can engage with the first internal spline, thereby controlling the rotation of the tensioning nut 1 and tightening the tensioning nut 1 onto the turbine shaft 7; and since an external thread is arranged at the front end of the turbine shaft 7, an internal threaded portion 13 is arranged on the inner side of the rear section of the tensioning nut 1, so that the internal threaded portion 13 can be threadedly connected to the front end of the turbine shaft 7.

[0032] When the tensioning nut 1 is connected to the low-pressure turbine shaft 7, in order to ensure the stability of the connection of the tensioning nut 1 and to prevent the rotor from shaking and loosening during operation, it is necessary to design a corresponding self-locking structure. The self-locking structure in this embodiment includes a nut locking member 2, a turbine shaft locking member 6, an annular stopper 5, a pin and other components, and the relative position of the tensioning nut 1 and the turbine shaft 7 is locked through the cooperation of these components, thereby preventing the tensioning nut 1 from loosening.

[0033] The turbine shaft locking member 6 is in a circular ring shape. The turbine shaft locking member 6 is fixed to the front end of the turbine shaft 7 when in use. Specifically, a turbine shaft locking spline 62 is provided on the outer side of the front end of the turbine shaft locking member 6, and a shaft end spline tooth 72 is provided on the front end of the turbine shaft 7. The turbine shaft locking spline 62 and the shaft end spline tooth 72 are key-connected to each other (i.e., the turbine shaft locking spline 62 and the shaft end spline tooth 72 are engaged with each other at the key groove).

[0034] The nut locking member 2 is arranged on the inner side of the turbine shaft locking member 6, and the nut locking member 2 can slide forward and backward relative to the axial direction of the turbine shaft locking member 6, so that the nut locking member 2 can be placed in the unlocking position or the locking position. When the nut locking member 2 is in the unlocking position, the tensioning nut 1 can rotate relative to the turbine shaft locking member 6, so that the tensioning nut 1 can be tightened to the front end of the turbine shaft 7; when the nut locking member 2 is in the locking state, the nut locking member 2 can be splined with the tensioning nut 1 and the turbine shaft locking member 6 at the same time.

[0035] A nut locking spline 21 is arranged on the outer side of the front end of the nut locking piece 2; an inner locking spline 61 is arranged on the inner side of the front end of the turbine shaft locking piece 6; a nut second spline 12 is arranged on the inner side of the front end of the tightening nut 1; when the nut locking piece 2 is in the locking position, the front end of the nut locking spline 21 is connected to the nut second spline 12, and the rear end is connected to the inner locking spline 61.

[0036] A compression spring 3 is arranged between the turbine shaft locking piece 6 and the nut locking piece 2. The front end of the nut locking piece 2 is provided with an outward turning edge 22, and the rear end of the turbine shaft locking piece 6 is provided with an inward turning edge 63. The front end of the compression spring 3 abuts against the outward turning edge 22, and the rear end abuts against the inward turning edge 63.

[0037] The rear end of the nut locking member 2 is fixedly connected to an annular stopper 5 through a pin 4, and the annular stopper 5 can abut against the rear end of the turbine shaft locking member 6 to limit the relative sliding position of the nut locking member 2 and the turbine shaft locking member 6. When the rear end of the nut locking member 2 is pressed against the annular stopper 5 under the elastic force of the compression spring 3, the nut locking member 2 can be prevented from moving backward again.

[0038] The outer diameter of the turbine shaft locking member 6 is not greater than the outer diameter of the front end of the turbine shaft 7, so that the turbine shaft locking member 6 can be withdrawn backward from the compressor rear journal 8 along with the turbine shaft 7. The outer diameter of the nut locking member 2 is not greater than the outer diameter of the front end of the turbine shaft 7, so that the nut locking member 2 can be withdrawn backward from the compressor rear journal 8 along with the turbine shaft 7. When the turbine shaft 7 is disassembled, the turbine shaft locking member 6 and the nut locking member 2 can be taken out from the rear end of the compressor rear journal 8, thereby providing conditions for the replacement and maintenance of the self-locking structure.

[0039] The rear end of the tension nut 1 may be provided with a nut cone surface 14, which corresponds to the journal cone surface 81 provided on the inner side of the compressor rear journal 8. When the tension nut 1 is connected to the low-pressure turbine shaft 7, the nut cone surface 14 fits with the journal cone surface 81, and through the inclined surface matching relationship between the two, the tension nut 1 can adjust the axial center position of the compressor rear journal 8 when tightened, thereby reducing the axial distance between the compressor rear journal 8 and the turbine shaft 7.

[0040] Example 2

[0041] Based on the structure of Example 1, the method for using the self-locking structure includes the following steps:

[0042] In the first step, the self-locking structure is first assembled to the front end of the turbine shaft 7, and the turbine shaft locking spline 62 on the turbine shaft locking member 6 is connected to the shaft end spline tooth 72 at the front end of the turbine shaft 7, and then the tensioning nut 1 is assembled and initially screwed to the front end of the turbine shaft 7.

[0043] In the second step, a professional tool is used to push the nut locking member 2 backward so that the front end of the nut locking member 2 is retracted into the front end of the turbine shaft locking member 6. The spline on the professional tool is key-connected with the first spline 11 of the nut on the tensioning nut 1, thereby driving the tensioning nut 1 to be tightened onto the turbine shaft 7.

[0044] The third step is to move the professional tool forward so that the compression spring 3 can push the nut locking piece 2 forward, so that the nut locking spline 21 of the nut locking piece 2 can be connected to the nut second spline 12.

[0045] The above embodiments are merely examples for the purpose of clarifying the description, and are not intended to limit the implementation methods; it is not necessary and impossible to list all implementation methods exhaustively. However, obvious changes or modifications derived therefrom are still within the scope of protection of the present technology.

Claims

1. A self-locking structure for a low-pressure rotor of a gas turbine, characterized in that: It comprises a nut locking member (2) and a turbine shaft locking member (6); The low-pressure rotor comprises a compressor rotor (9) and a turbine rotor (10); the rear end of the compressor rotor (9) has a compressor rear journal (8), and the turbine rotor (10) has a turbine shaft (7); the compressor rear journal (8) and the front end of the turbine shaft (7) are sleeve-connected, and the front end of the turbine shaft (7) is threadedly connected with a tensioning nut (1), and the tensioning nut (1) fixes the relative position of the compressor rear journal (8) and the turbine shaft (7); The turbine shaft locking member (6) is annular in shape and fixed to the front end of the turbine shaft (7); the nut locking member (2) is arranged on the inner side of the turbine shaft locking member (6) and can slide relative to the axial direction of the turbine shaft locking member (6) so that the nut locking member (2) is placed in an unlocking position or a locking position; when the nut locking member (2) is in the unlocking position, the tensioning nut (1) can rotate relative to the turbine shaft locking member (6) so that the tensioning nut (1) is tightened to the front end of the turbine shaft (7); when the nut locking member (2) is in a locked state, the nut locking member (2) can simultaneously engage with the tensioning nut (1) and the turbine shaft locking member (6) by splines.

2. The self-locking structure of the low-pressure rotor of a gas turbine according to claim 1, characterized in that: The outer diameter of the turbine shaft locking piece (6) is not greater than the outer diameter of the front end of the turbine shaft (7), so that the turbine shaft locking piece (6) can be withdrawn backwards along with the turbine shaft (7) to the rear journal (8) of the compressor.

3. The self-locking structure of the low-pressure rotor of a gas turbine according to claim 2, characterized in that: The outer diameter of the nut locking piece (2) is not greater than the outer diameter of the front end of the turbine shaft (7), so that the nut locking piece (2) can be withdrawn backwards along with the turbine shaft (7) to the rear journal (8) of the compressor.

4. The self-locking structure of the low-pressure rotor of a gas turbine according to claim 2, characterized in that: A turbine shaft locking spline (62) is provided on the outer side of the front end of the turbine shaft locking member (6), and a shaft end spline tooth (72) is provided on the front end of the turbine shaft (7), and the turbine shaft locking spline (62) and the shaft end spline tooth (72) are key-connected to each other.

5. The self-locking structure of the low-pressure rotor of a gas turbine according to any one of claims 1 to 4, characterized in that: A nut cone surface (14) is provided on the outer side of the rear end of the tensioning nut (1), and a journal cone surface (81) is provided on the inner side of the compressor rear journal (8); the nut cone surface (14) can fit with the journal cone surface (81) to adjust the axis of the compressor rear journal (8) when the tensioning nut (1) is tightened.

6. The self-locking structure of the low-pressure rotor of a gas turbine according to any one of claims 1 to 4, characterized in that: A nut locking spline (21) is arranged on the outer side of the front end of the nut locking member (2); an inner locking spline (61) is arranged on the inner side of the front end of the turbine shaft locking member (6); and a nut second spline (12) is arranged on the inner side of the front end of the tensioning nut (1); when the nut locking member (2) is in the locking position, the front end of the nut locking spline (21) is connected to the nut second spline (12) and the rear end is connected to the inner locking spline (61).

7. The self-locking structure of the low-pressure rotor of a gas turbine according to claim 6, characterized in that: A compression spring (3) is arranged between the turbine shaft locking member (6) and the nut locking member (2); the front end of the nut locking member (2) is provided with an outward-turned edge (22); the rear end of the turbine shaft locking member (6) is provided with an inward-turned edge (63); the front end of the compression spring (3) abuts against the outward-turned edge (22), and the rear end abuts against the inward-turned edge (63).

8. The self-locking structure of the low-pressure rotor of a gas turbine according to claim 7, characterized in that: The rear end of the nut locking member (2) is fixedly connected to an annular stopper (5) via a pin (4); the annular stopper (5) can abut against the rear end of the turbine shaft locking member (6) to limit the relative sliding position of the nut locking member (2) and the turbine shaft locking member (6).

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