A testing device for a gas turbine sealing structure

Abstract

The present invention belongs to the technical field of gas turbines, and particularly relates to a gas turbine seal structure testing device, which includes an intake end cover plate, a flexible contact seal, a metal seal positioning ring, a pre-whirl generator, an intake end housing, a first test seal, a second test seal, an exhaust end housing, a rotor shaft, a lifting eye bolt, an intake end long bolt, a housing long bolt, and a positioning pin; the intake end cover plate, the flexible contact seal, the metal seal positioning ring, the pre-whirl generator, the intake end housing, the first test seal, the second test seal, and the exhaust end housing are sequentially installed on the rotor shaft; the intake end long bolt is installed on the intake end housing; the intake end housing and the exhaust end housing are fastened by the housing long bolt; the lifting eye bolt is installed on the circumferences of the intake end housing and the exhaust end housing. This testing device is provided with a pre-whirl generator and can be used as a single module for adding a seal structure testing device to various types of rotor test benches.

Description

Technical Field

[0001] The present invention belongs to the technical field of gas turbines, and particularly relates to a test device for a gas turbine seal structure. Background Art

[0002] Gas turbines and steam turbines are two common types of large rotating machinery. Whether the working medium of the engine is gas itself or steam, when the engine is operating, there are significant leakage phenomena between different-stage blades, between the rotor shaft and the housing, and between the blade tips and the housing, resulting in a reduction in working efficiency.

[0003] The wisdom of traditional industry is to install certain contact or non-contact seal structures on the outer side of the rotor shaft or the inner side of the housing at positions where large leakage is likely to occur to reduce the leakage of the working medium. However, the addition of the seal structure has an impact on the rotor system in the form of additional aerodynamic excitation forces. Therefore, when conducting experimental research and testing on the seal structure, not only the leakage performance of the seal structure needs to be considered, but also the dynamic characteristics of the seal structure should be incorporated into the comprehensive evaluation index.

[0004] Traditional seal test benches generally can only obtain the dynamic and leakage performance of the seal structure under straight-through intake or vertical intake, and it is difficult to obtain the characteristic parameters of the seal structure under more complex conditions considering different pre-rotations. At the same time, traditional test devices generally load the working medium in a way that the medium enters from the middle and exits at both ends. Even if a pre-rotation generating device is provided in the intake cavity, it is impossible to ensure that the rotor is affected by a completely symmetric loading condition at both ends of the outlet, resulting in the inability to more comprehensively test the characteristics of the seal structure. Summary of the Invention

[0005] In order to solve the above technical problems, the present invention provides a test device for a gas turbine seal structure. The test device is provided with a pre-rotation generator and can be used as a single module for adding to various types of rotor test benches as a seal structure test device. While meeting the requirements of traditional straight-through intake, it is designed as a chamber structure that allows the working medium to move unidirectionally, and a pre-rotation generator that can be added and replaced is introduced, supporting the complex working condition requirements of the seal structure test system under intake conditions including no pre-rotation, positive pre-rotation, and reverse pre-rotation, providing a new idea for the design of a gas turbine seal structure test device.

[0006] The technical solution adopted by the present invention is as follows: a gas turbine sealing structure testing device, which includes an intake end cover plate, a flexible contact seal, a metal seal positioning ring, a pre-whirl generator, an intake end housing, a first test seal, a second test seal, an exhaust end housing, a rotor shaft, lifting eye bolts, intake end long bolts, housing long bolts, nuts and positioning pins; the intake end cover plate, the flexible contact seal, the metal seal positioning ring, the pre-whirl generator, the intake end housing, the first test seal, the second test seal and the exhaust end housing are sequentially installed on the rotor shaft; the intake end long bolts are installed on the intake end housing after passing through the intake end cover plate and the metal seal positioning ring; the intake end housing and the exhaust end housing are fastened by the housing long bolts and nuts; the lifting eye bolts are respectively installed on the circumferences of the intake end housing and the exhaust end housing; the first test seal and the second test seal are assembled together by the positioning pins.

[0007] Further, the pre-whirl generator is internally designed with periodically inclined slots, which can enable the airflow outside the ring to obtain circumferential flow velocity through the periodically inclined slots, thereby playing a role in exciting pre-whirl.

[0008] Further, after the first test seal and the second test seal are assembled by a series of positioning pins, they are sleeved on the rotor shaft between the intake end housing and the exhaust end housing, and a certain gap is reserved between the first test seal and the second test seal and the rotor shaft. This gap is one of the adjustable parameters of the test system and can be adjusted by matching different diameters of the rotor shaft with the first test seal and the second test seal of different sizes.

[0009] Further, the number of lifting eye bolts on the intake end housing is 4, and they are evenly distributed in a circle; the number of lifting eye bolts on the exhaust end housing is 4, and they are evenly distributed in a circle.

[0010] Further, the 4 lifting eye bolts on the intake end housing and the 4 lifting eye bolts on the exhaust end housing are symmetrically distributed.

[0011] Further, the number of intake end long bolts is 8.

[0012] Further, the number of housing long bolts is 8.

[0013] Advantages of the present invention: A gas turbine seal structure testing device is provided. The testing device is equipped with a pre-whirl generator and can be used as a single module for adding a seal structure testing device to various types of rotor test benches. While meeting the requirements of traditional direct-through air intake, it is designed as a chamber structure that allows the working medium to move unidirectionally, and a pre-whirl generator that can be added and replaced is introduced, supporting the complex working conditions of the seal structure testing system under the conditions of no pre-whirl, positive pre-whirl, and reverse pre-whirl air intake, providing a new idea for the design of the gas turbine seal structure testing device. Description of the Drawings

[0014] Figure 1 is the three-dimensional disassembly drawing of Embodiment 1;

[0015] Figure 2 is the three-dimensional assembly drawing of Embodiment 1;

[0016] Figure 3 is Figure 2 the side view of

[0017] Figure 4 is Figure 3 the sectional view taken along A-A in

[0018] Figure 5 is Figure 3 the sectional view taken along B-B in

[0019] Figure 6 is Figure 3 the sectional view taken along C-C in

[0020] Figure 7 is Figure 3 the sectional view taken along D-D in Detailed Embodiments

[0021] Embodiment 1

[0022] Referring to the various figures, a test device for a gas turbine sealing structure, the test device includes an inlet end cover plate 1, a flexible contact seal 2, a metal seal positioning ring 3, a pre-whirl generator 4, an inlet end housing 5, a first test seal 6, a second test seal 7, an outlet end housing 8, a rotor shaft 9, lifting eye bolts 10, inlet end long bolts 11, housing long bolts 12, nuts 13 and positioning pins 14; the inlet end cover plate 1, the flexible contact seal 2, the metal seal positioning ring 3, the pre-whirl generator 4, the inlet end housing 5, the first test seal 6 and the second test seal 7, and the outlet end housing 8 are sequentially installed on the rotor shaft 9; the inlet end long bolts 11 pass through the inlet end cover plate 1 and the metal seal positioning ring 3 and are installed on the inlet end housing 5; the inlet end housing 5 and the outlet end housing 8 are fastened by the housing long bolts 12 and the nuts 13; the lifting eye bolts 10 are respectively installed on the circumferences of the inlet end housing 5 and the outlet end housing 8; the first test seal 6 and the second test seal 7 are assembled together by the positioning pins 14; the pre-whirl generator 4 is provided with inclined grooves; there is a gap between the assembled first test seal 6 and the second test seal 7 and the rotor shaft 9; the number of lifting eye bolts 10 on the inlet end housing 5 is 4, and they are evenly distributed in the circumferential direction; the number of lifting eye bolts 10 on the outlet end housing 8 is 4, and they are evenly distributed in the circumferential direction; the 4 lifting eye bolts 10 on the inlet end housing 5 and the 4 lifting eye bolts 10 on the outlet end housing 8 are symmetrically distributed; the number of inlet end long bolts 11 is 8; the number of housing long bolts 12 is 8.

[0023] During installation, in sequence according to the order of the inlet end cover plate, the flexible contact seal, the metal sealing ring, the pre-whirl generator, and the inlet end housing, it is sleeved on the rotor shaft. Then, the first test seal and the second test seal are assembled through a series of positioning pins, and after the assembly is completed, it is sleeved on the rotor shaft from the opposite side and pushed to the groove reserved in the inlet end housing to fit tightly. Then, the outlet end housing is sleeved on the rotor shaft from the opposite side and pushed to a position where it fits tightly with the inlet end housing, and then the long bolts for housing fixing and the nuts for housing fixing are used to fix and install through the installation holes reserved at the edge positions of the inlet end housing and the outlet end housing. Finally, 4 groups of lifting eye bolts symmetrically arranged in the horizontal and vertical directions are respectively installed in the threaded holes preset on the surfaces of the inlet end housing and the outlet end housing, and the assembly of the test device for the gas turbine sealing structure can be completed.

[0024] When conducting the test, the device needs to be hoisted by elastic supports into any frame with an outer diameter larger than that of the device. And at Figure 2 several air inlets preset in the circumferential direction of the inlet end housing as shown, install an air flow meter and connect it to an external air pump, and the air flow is as Figure 4As shown, the circumferential velocity is obtained through the pre-whirl generator to form a pre-whirl air flow, which then sequentially passes unidirectionally through the circumferential clearance between the intake end housing, the first test seal, the second test seal, and the outlet end housing and the rotor shaft, and is then discharged into the relatively constant atmospheric pressure. By reading the values of the externally connected sensors and corresponding calculations, the dynamic characteristics of the sealing structure can be obtained.

[0025] The gas turbine sealing structure test device has the characteristics of single-sided intake and opposite-side outlet. The air flow path is relatively fixed, and there are fewer system interferences that may cause additional impacts. At the same time, by not installing or replacing the pre-whirl generator with different angled inclined slots, the test conditions of the sealing structure can be controlled to be non-pre-whirl, positive pre-whirl, or negative pre-whirl, which can bring richer working conditions for the test of the sealing structure, and thus improve the research on the leakage and dynamic performance of the sealing structure.

[0026] The working medium enters the surface of the pre-whirl generator through several intake ports circumferentially arranged on the intake end housing. The air flow after pre-whirl excitation then passes through the intake end housing, the first test seal, the second test seal, and the outlet end housing respectively and is then discharged into the atmosphere. In the upstream area of the intake end housing, a metal sealing locating ring is used to fasten the pre-whirl generator, and the contact position between the intake end housing and the intake end cover plate is sealed. At the same time, a flexible contact seal is used to further seal the intake cavity and the rotor shaft to ensure the unidirectional flow of the air flow in the test area. The flexible contact seal, the metal sealing locating ring, the pre-whirl generator, and the intake end cover plate are all fixedly installed on the intake end housing through long bolts for intake end fixation.

[0027] The gas turbine sealing structure test device can obtain different pre-whirl working conditions by installing pre-whirl generators of different models, or can obtain the basic direct-through test air flow by not installing the pre-whirl generator. At the same time, 4 groups of lifting ring bolts are installed on the outer circumference of the intake end housing and the outlet end housing to arrange elastic force signal probes and displacement sensors, and are hoisted and suspended in any circumferential hanger that meets the outer dimensions of the device. The seals under complex and variable working conditions such as different intake pressures, rotor speeds, and whirling radii (controlled by adjusting the tightness of the symmetric lifting ring ropes) are tested. Moreover, it can be directly installed in a fixed manner on the rotor test bench to directly obtain the dynamic characteristics of the rotor, which can meet rich test requirements.

[0028] Aspects of the present technical solution are described with reference to the accompanying drawings in this disclosure, and many illustrative embodiments are shown in the drawings. The embodiments of the technical solution are not necessarily intended to include all aspects of the present technical solution. It should be understood that the various concepts and embodiments introduced above, as well as those concepts and implementations described in more detail below, can be implemented in any of many ways, because the concepts and embodiments disclosed in the present technical solution are not limited to any implementation. Additionally, some aspects disclosed in the present technical solution can be used alone, or in any suitable combination with other aspects disclosed in the present technical solution.

[0029] Although the present technical solution has been disclosed above with preferred embodiments, it is not intended to limit the present technical solution. Those with ordinary knowledge in the technical field to which the present technical solution pertains can make various changes and modifications without departing from the spirit and scope of the present technical solution. Therefore, the protection scope of the present technical solution shall be defined by the claims.

Claims

1. A testing device for a gas turbine sealing structure, characterized in that: the testing device includes an intake end cover plate (1), a flexible contact seal (2), a metal seal positioning ring (3), a pre-whirl generator (4), an intake end housing (5), a first test seal (6), a second test seal (7), an exhaust end housing (8), a rotor shaft (9), lifting eye bolts (10), intake end long bolts (11), housing long bolts (12), nuts (13) and positioning pins (14); the intake end cover plate (1), the flexible contact seal (2), the metal seal positioning ring (3), the pre-whirl generator (4), the intake end housing (5), the first test seal (6) and the second test seal (7), and the exhaust end housing (8) are sequentially installed on the rotor shaft (9); the intake end long bolts (11) pass through the intake end cover plate (1) and the metal seal positioning ring (3) and are installed on the intake end housing (5); the intake end housing (5) and the exhaust end housing (8) are fastened by housing long bolts (12) and nuts (13); the lifting eye bolts (10) are respectively installed on the circumferences of the intake end housing (5) and the exhaust end housing (8); the first test seal (6) and the second test seal (7) are assembled together by positioning pins (14); the pre-whirl generator (4) is provided with inclined grooves inside.

2. The testing device for a gas turbine sealing structure according to claim 1, characterized in that: a gap is left between the assembled first test seal (6) and second test seal (7) and the rotor shaft (9).

3. The testing device for a gas turbine sealing structure according to claim 1, characterized in that: the number of lifting eye bolts (10) on the intake end housing (5) is 4, and they are evenly distributed in a circumferential manner; the number of lifting eye bolts (10) on the exhaust end housing (8) is 4, and they are evenly distributed in a circumferential manner.

4. The testing device for a gas turbine sealing structure according to claim 3, characterized in that: the 4 lifting eye bolts (10) on the intake end housing (5) and the 4 lifting eye bolts (10) on the exhaust end housing (8) are symmetrically distributed.

5. The testing device for a gas turbine sealing structure according to claim 1, characterized in that: the number of intake end long bolts (11) is 8.

6. The testing device for a gas turbine sealing structure according to claim 1, characterized in that: the number of housing long bolts (12) is 8.

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