High-temperature air tightness testing device and testing method for baseline type sealing element

Abstract

The invention discloses a high-temperature air tightness testing device and testing method for a baseline type sealing element, and relates to the technical field of sealing element performance testing. The sliding table movement module and the friction movement module are assembled in the longitudinal area and the transverse area of the machine base respectively, the sliding table movement module is provided with a sliding table, the friction movement module is provided with a push-pull plate, displacement is controlled through a reciprocating executing mechanism, the push-pull plate fixes a friction plate, the sealing piece clamp set comprises three layers of sealing piece clamps, and the outer layer is fixed to the end of the sliding table. A first sealing groove is machined, an anti-leakage sealing piece is installed, an exhaust emission hole is further machined, a second sealing groove is machined in the middle layer, a third sealing groove is machined in the inner layer and used for installing a sealing piece to be detected, and a sealing cavity air inlet is formed in the inner layer and connected with air supply. Through cooperative work of the sliding table motion module and the friction motion module and combination of the ingenious design of the sealing element clamp set, static and dynamic leakage amount testing under different working conditions can be achieved, and richer data support is provided for research of a baseline type sealing element leakage mechanism.

Description

Technical Field

[0001] The present invention relates to the technical field of seal performance testing, and particularly to a high-temperature airtightness testing device and method for baseline seals. Background Art

[0002] As a key component in high-temperature gas sealing technology, baseline seals are widely used and play an important role in the aerospace field. For example, during the operation of reusable aircraft, high-temperature gas flow may penetrate into the interior through gaps and moving parts, posing a potential threat to the safety and reliability of the aircraft. At the same time, in gas turbines, at the interfaces or connections of fixed components such as combustion chambers, nozzles, and fairings, especially at positions passing through internal cooling flow paths, high-temperature gas seals are also required to ensure sealing performance. Currently, the research on baseline sealing technology mainly focuses on the analysis of a single physical field (such as the flow field). However, in practical applications, the performance of seals is often significantly affected by the coupling effects of multiple physical fields such as mechanics, heat transfer, and fluid dynamics. Due to insufficient experimental data and significant differences between experimental conditions and actual working conditions in existing research, it is difficult to fully guarantee the accuracy of experimental results. Therefore, constructing a high-temperature airtightness testing device that can be used to simulate the real working environment of baseline seals has important research significance and application value.

[0003] Among the existing domestic high-temperature gas seal leakage testing platforms, the Chinese invention authorization patent with the application number CN202210425942.9 discloses a high-temperature airtightness testing system and method for W-shaped metal seals used in aerospace vehicles. It realizes high-temperature gas seal leakage testing through a tester body, an upper and lower backplane heating control system, an external air supply regulation system, and an automated measurement and control system based on PLC and a human-machine interface. Among them, the tester body uses upper and lower backplane heaters to simulate a high-temperature environment, and installs the W-shaped metal seal through a high-precision positioning block; the external air supply regulation system provides stable compressed air, enabling gas to leak from the outside to the inside along the annular seal specimen. After the leaked gas is cooled by a coil heat exchanger, the leakage flow rate and temperature are measured in real time by a high-precision thermal flowmeter; the automated measurement and control system based on PLC and a human-machine interface realizes the automated monitoring and regulation of temperature, pressure, and flow rate. Although this invention can achieve high-temperature gas static seal leakage testing, it cannot perform high-temperature gas dynamic seal leakage testing, there is a certain difference from the actual working scenario, it is difficult to truly simulate the working environment, and the backplane heating method requires a long heating time, resulting in a significant increase in the test cycle. Summary of the Invention

[0004] In order to address the shortcomings of the background technology, the present invention provides a high-temperature air tightness testing device and a testing method for baseline seals. Through the coordinated work of the slide motion module and the friction motion module, combined with the ingenious design of the seal fixture group, it can realize static and dynamic leakage tests under different working conditions, and provide more abundant data support for the research on the leakage mechanism of baseline seals.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A high-temperature airtightness test device for a baseline seal comprises a machine base, a seal fixture group, a slide motion module and a friction motion module. The machine base is an L-shaped structure on a plane, and its longitudinal region and transverse region respectively carry the assembly slide motion module and the friction motion module. The slide motion module is provided with a slide that can be displaced in the longitudinal direction. The friction motion module is laterally provided with a push-pull plate at a middle transfer position of the machine base and its displacement is controlled by a reciprocating actuator. The front of the push-pull plate can be detachably fixed with a friction plate, and a circular protrusion is provided in the middle of the friction plate for contact support of the seal to be tested. The seal fixture group comprises an outer layer coaxially assembled and fixed from outside to inside. A sealing fixture, a middle-layer sealing fixture and an inner-layer sealing fixture, wherein the outer-layer sealing fixture is fixed to the end of the slide, the first sealing groove is processed on the positive end face and an anti-leakage seal is installed, when the sealing fixture group contacts the friction plate, the anti-leakage seal is spaced around the circular protrusion to form a test sealing cavity, the outer-layer sealing fixture is also processed to set an exhaust gas discharge hole, the second sealing groove is processed on the positive end face of the middle-layer sealing fixture, the third sealing groove is processed on the positive end face of the inner-layer sealing fixture, the second sealing groove and the third sealing groove are used to install the seal to be tested, and the inner-layer sealing fixture has a sealing cavity air inlet connected to the air supply on the back end face.

[0007] Furthermore, the slide motion module includes a slide, a longitudinal linear guide and an electric cylinder. The longitudinal linear guides are fixed in parallel on both sides of the longitudinal area of ​​the machine base. The slide consists of a slide body and two wing plates. The slide body is a cylindrical structure and is arranged longitudinally between the longitudinal linear guides. The two wing plates are fixed on both sides of the outer wall of the slide body and are slidably connected to the longitudinal linear guide. The electric cylinder is arranged at the bottom of the slide and is connected and fixed to the machine base. The telescopic end of the electric cylinder is connected and fixed to the bottom of the slide body.

[0008] Furthermore, the friction motion module includes a reciprocating actuator, a tension and compression sensor, a transverse linear guide and a push-pull plate. The transverse linear guide is fixed in parallel up and down at the middle transfer position of the machine base. The back of the push-pull plate is slidably connected to the transverse linear guide. The reciprocating actuator is arranged in the lateral area of ​​the machine base to control the push-pull plate to move back and forth along the transverse linear guide. The tension and compression sensor is set at the connection between the reciprocating actuator and the push-pull plate.

[0009] Further, the reciprocating actuator includes a driving motor, a runner, a crank connecting rod and a linear bearing. The driving motor is fixedly connected to the machine base. The runner is coaxially fixed to the output shaft of the driving motor. The linear bearing is fixedly connected to the machine base and is provided with a joint pull rod. One end of the joint pull rod is connected to the side of the push-pull plate through a tension and compression sensor. The two ends of the crank connecting rod are respectively hinged to the other end of the joint pull rod and the eccentric shaft provided on the runner.

[0010] Further, gaskets are arranged in the third sealing groove of the inner layer seal fixture to adapt to seal specimens of different sizes.

[0011] Further, cooling water channels are machined on the side wall of the inner layer seal fixture, and water inlet holes and drain holes are provided in through connection with the back end face of the inner layer seal fixture.

[0012] A high-temperature airtightness test method for a baseline seal includes the following steps:

[0013] Step 1: Installation of the seal specimen to be tested

[0014] According to the requirements of single-seal leakage test or double-seal leakage test, the seal specimen to be tested is installed in the third sealing groove or the second and third sealing grooves of the seal fixture group.

[0015] Step 2: Construction of the test seal cavity

[0016] The slide is controlled by the slide movement module to drive the seal fixture group to displace towards the friction plate until the seal specimen to be tested contacts the circular protrusion of the friction plate and reaches a predetermined compression amount. Meanwhile, the anti-leakage seals installed in the first sealing groove are in spaced contact around the circular protrusion of the friction plate to form a test seal cavity.

[0017] Step 3: Gas injection and experimental analysis

[0018] High-temperature and high-pressure gas with a temperature of 20 - 400°C and a pressure below 3 Mpa is injected into the test seal cavity through the air inlet of the seal cavity. Temperature sensors and pressure sensors are used for data acquisition. When the pressure in the test seal cavity reaches the preset value and remains stable, the gas supply is stopped and pressure is maintained. For the static leakage amount test, the pressure data change in the test seal cavity is directly recorded in real time, and the leakage amount of the seal specimen to be tested is calculated based on the gas state equation. For the dynamic leakage amount test, the friction movement module is started during the pressure maintenance stage after the gas supply is stopped, and the circular protrusion of the friction plate repeatedly rubs the seal specimen to be tested within the range of the anti-leakage seal.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: By controlling the displacement of the sliding table through the sliding table motion module, the compression amount of the seal to be tested can be accurately controlled. By controlling the movement of the friction plate through the friction motion module, the test can be switched from the static leakage amount to the dynamic leakage amount, filling the technical gap that the current test platform only evaluates the static sealing performance and lacks dynamic sealing tests. By replacing different friction plates and adjusting the moving speed of the friction motion module, the correlation between the leakage amount of the seal to be tested and the surface roughness and friction rate of the friction surface can be assisted in research. A cooling water channel is arranged in the inner seal fixture of the seal fixture group to assist in researching the influence of cooling conditions on the sealing performance of the seal to be tested, so as to realize the leakage test of the baseline seal under different working conditions, with the multi-parameter test ability of temperature, pressure, compression amount, surface roughness of the friction surface, friction rate and cooling conditions, providing richer data support for the research on the leakage mechanism of the baseline seal. The overall system is simple and reasonable, the adjustment of state parameters is convenient, the repeatability is good, and the accuracy is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is the overall structural schematic diagram of the high-temperature airtightness test device of the present invention;

[0021] Figure 2 is the gas pipeline connection diagram of the high-temperature airtightness test device of the present invention;

[0022] Figure 3 is the assembly structural schematic diagram of the sliding table motion module in the present invention;

[0023] Figure 4 is the split structural schematic diagram of the seal fixture group in the present invention;

[0024] Figure 5 is the back structural schematic diagram of the inner seal fixture in the present invention;

[0025] Figure 6 is the assembly structural schematic diagram of the friction motion module in the present invention.

[0026] In the figure: 1 - machine base, 2 - seal fixture group, 3 - sliding table, 4 - longitudinal linear guide rail, 5 - electric cylinder, 6 - lifting ring, 7 - reciprocating actuator, 8 - tension and compression sensor, 9 - friction plate, 10 - transverse slider, 11 - transverse linear guide rail, 12 - push-pull plate, 13 - support box, 14 - longitudinal slider, 15 - connecting piece, 201 - outer seal fixture, 202 - middle seal fixture, 203 - inner seal fixture, 2011 - first seal groove, 2012 - exhaust gas discharge hole, 2021 - second seal groove, 2031 - third seal groove, 2032 - seal cavity air inlet, 2033 - cooling water channel, 301 - sliding table body, 302 - wing plate, 701 - drive motor, 702 - runner, 703 - crank connecting rod, 704 - linear bearing. Detailed implementation manners

[0027] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0028] As Figures 1 to 6 shown, a high-temperature airtightness test device for a baseline seal includes a machine base 1, a seal fixture group 2, a sliding table motion module, and a friction motion module. Among them, the machine base 1 serves as the base of the entire device to carry other components, and has an L-shaped structure on the plane. Its longitudinal area is used to carry and assemble the sliding table motion module, and its transverse area is used to carry and assemble the friction motion module. A support box 13 is arranged along the transverse direction at the intermediate transfer position for carrying the push-pull plate 12 in the friction motion module, so that the sliding table motion module and the friction motion module can work together. In addition, a transparent heat insulation plate can be installed around the device as an overall protective cover to prevent the leaked high-temperature and high-pressure gas from causing harm to experimental personnel and surrounding facilities.

[0029] Combined with Figure 1 、 Figure 3As shown, the slide table movement module is used to precisely control the compression amount of the seal to be tested, and includes a slide table 3, a longitudinal linear guide rail 4, and an electric cylinder 5. The longitudinal linear guide rail 4 is fixed on both sides of the longitudinal area of the machine base 1 in parallel by screws to guide the longitudinal movement of the slide table 3. The slide table 3 is composed of a slide table main body 301 and two wing plates 302. The slide table main body 301 is a cylindrical structure and is arranged longitudinally between the longitudinal linear guide rails 4. A lifting ring 6 can be installed on the top of the slide table main body 301 to facilitate lifting operations. The two wing plates 302 are fixedly arranged on both sides of the outer wall of the slide table main body 301 and are respectively slidably connected to the longitudinal linear guide rail 4 through longitudinal sliders 14. The electric cylinder 5 is arranged at the bottom of the slide table 3 and is fixed to the machine base 1 by screws. The telescopic end of the electric cylinder 5 is connected and fixed to the middle position of the bottom of the slide table main body 301 through a connecting piece 15. The electric cylinder 5 is equipped with a controller that can precisely adjust the displacement amount of the slide table 3, and its repeat positioning accuracy can reach ±0.02 mm to control the stable linear movement of the slide table 3 along the longitudinal linear guide rail 4, thereby precisely adjusting the compression amount of the seal to be tested.

[0030] Combined with Figure 1 、 Figure 6As shown, the friction motion module is used for the dynamic leakage measurement of the seal to be tested, so as to study the correlation between the leakage of the seal to be tested, the friction rate and the surface roughness of the friction surface. It includes a reciprocating actuator 7, a tension-compression sensor 8, a horizontal linear guide 11 and a push-pull plate 12. The horizontal linear guide 11 is fixedly installed on the surface of the wall plate of the support box 13 in parallel up and down by screws. The back of the push-pull plate 12 is slidably connected to the horizontal linear guide 11 through a horizontal slider 10. A lifting ring 6 can be installed on the top of the push-pull plate 12 for easy hoisting operation. A friction plate 9 is detachably fixed to the front of the push-pull plate 12. A circular protrusion is provided at the middle position of the friction plate 9 for the contact support of the seal to be tested, so as to ensure that the seal to be tested contacts the friction surface before the anti-leakage seal, thereby ensuring that the measured leakage is only the leakage of the seal to be tested. The reciprocating actuator 7 is arranged in the horizontal area of the machine base 1 to control the reciprocating displacement of the push-pull plate 12 along the horizontal linear guide 11. The tension-compression sensor 8 is arranged at the connection between the reciprocating actuator 7 and the push-pull plate 12 to monitor the change of the friction force during the friction process in real time, so as to provide experimental data support for the life prediction of the seal to be tested. The reciprocating actuator 7 includes a driving motor 701, a runner 702, a crank connecting rod 703 and a linear bearing 704. The housing of the driving motor 701 is fixedly connected to the machine base 1. The runner 702 is coaxially fixed to the output shaft of the driving motor 701. The linear bearing 704 is fixedly connected to the machine base 1 and is provided with a joint pull rod. One end of the joint pull rod is connected to the side of the push-pull plate 12 through the tension-compression sensor 8. Both ends of the crank connecting rod 703 are respectively hinged to the other end of the joint pull rod and the eccentric shaft provided on the runner 702. The friction rate can be precisely controlled by adjusting the rotation speed of the driving motor 701. The friction stroke can be flexibly adjusted by adjusting the length of the joint pull rod. The surface roughness of the friction surface can be switched by replacing different friction plates 9.

[0031] Combined with Figure 1 , Figures 4 to 5As shown in the figure, the seal fixture set 2 is used for the installation of the seal to be tested, and includes three-layer annular structures of an outer seal fixture 201, a middle seal fixture 202, and an inner seal fixture 203 that are coaxially assembled and fixed by screws from the outside to the inside. The front end faces of the three-layer annular structures are arranged flush. Among them, the outer seal fixture 201 is coaxially fixed to the end of the sliding table main body 301 by screws and moves synchronously with it. The front end face of the outer seal fixture 201 is machined with a first seal groove 2011 and an anti-leakage seal is installed. The anti-leakage seal uses a perfluoroether O-ring. The thickness of the perfluoroether O-ring should be greater than the thickness of the seal to be tested, and its projection is spaced around the circular protrusion of the friction plate 9 to prevent waste gas leakage, so that a test seal cavity is formed when the seal fixture set 2 contacts the friction plate 9. The outer seal fixture 201 is also machined with an exhaust gas discharge hole 2012. One end of the exhaust gas discharge hole 2012 communicates with the position on the front end face of the outer seal fixture 201 inside the first seal groove 2011, and the other end communicates with the outer side wall of the outer seal fixture 201. The exhaust gas can be discharged through the exhaust gas discharge hole 2012 and centrally introduced into the exhaust gas treatment equipment for treatment; the front end face of the middle seal fixture 202 is machined with a second seal groove 2021, and the front end face of the inner seal fixture 203 is machined with a third seal groove 2031. The second seal groove 2021 and the third seal groove 2031 are used for installing the seal to be tested. The back end face of the inner seal fixture 203 is provided with a seal cavity air inlet 2032. The seal cavity air inlet 2032 introduces high-temperature and high-pressure gas into the test seal cavity through a connecting gas pipeline. Here, the definition of high temperature is 20 - 400 °C, and the definition of high pressure is below 3 Mpa.

[0032] During the single-seal leakage test, only install the seal to be tested in the third seal groove 2031. The leakage test requirements of seals to be tested with different sizes can be met by setting gaskets in the third seal groove 2031.

[0033] During the double-seal leakage test, install the seals to be tested in the second seal groove 2021 and the third seal groove 2031 at the same time.

[0034] In addition, a cooling water channel 2033 can be arranged on the outer surface of the inner seal fixture 203. The cooling water channel 2033 is composed of a plurality of arc-shaped grooves arranged in a circumferentially staggered manner. A sealing fixing ring sleeve on the outer surface of the inner seal fixture 203 closes the openings of the plurality of arc-shaped grooves. Water inlet holes and drain holes are processed through the corresponding positions of the back end face of the inner seal fixture 203 and the first and last arc-shaped grooves. Two adjacent arc-shaped grooves between the head and the tail are connected through a processed water passing channel to measure the leakage of the seal to be tested under cooling conditions, so as to study the influence of cooling conditions on the sealing performance of the seal to be tested. This design not only enhances the flexibility and applicability of the test, but also provides more comprehensive data support for the performance research of the seal to be tested.

[0035] Combined with Figure 2 As shown, the gas pipeline is supplied with gas by a nitrogen cylinder and passes through a pressure reducing valve, an air filter, a high-temperature one-way valve, and a gas heater in sequence, and is divided into two branches through a tee joint. One branch passes through a stop valve one, a tee joint two equipped with a temperature sensor, and a tee joint three equipped with a pressure sensor in sequence and is connected to the sealing cavity air inlet 2032 to be introduced into the test sealing cavity. The temperature sensor and the pressure sensor are connected to a data acquisition card and the collected data is transmitted to the test software for analysis and processing. The other branch is provided with a stop valve two to discharge the remaining experimental gas, and is jointly connected to the waste gas treatment equipment for treatment with the waste gas discharged through the waste gas discharge hole 2012. The nitrogen cylinder provides gas with a certain pressure, and then the nitrogen is heated to the required temperature through the gas heater. To ensure the safety of the system, a high-temperature one-way valve is installed in the pipeline to prevent the gas from flowing back into the nitrogen cylinder and causing an explosion risk.

[0036] As Figures 1 to 6 shown, a high-temperature airtightness test method for a baseline seal includes the following steps:

[0037] Step 1: Installation of the seal to be tested

[0038] According to the requirements of single-seal leakage test or double-seal leakage test, install the seal to be tested in the third seal groove 2031 or the second seal groove 2021 and the third seal groove 2031 of the seal fixture group 2;

[0039] Step 2: Construction of the test sealing cavity

[0040] Control the slide 3 to drive the seal fixture group 2 to displace towards the friction plate 9 through the slide movement module until the seal to be tested contacts the circular protrusion of the friction plate 9 and reaches the predetermined compression amount. At the same time, the anti-leakage seal installed in the first seal groove 2011 contacts and surrounds the circular protrusion of the friction plate 9 at intervals to form a test sealing cavity;

[0041] Step 3: Gas introduction and experimental analysis

[0042] Introduce high-temperature and high-pressure gas with a temperature ranging from 20 to 400 °C and a pressure below 3 Mpa into the test sealing cavity through the air inlet 2032 of the sealing cavity. Use temperature sensors and pressure sensors for data acquisition. After the pressure in the test sealing cavity reaches the preset value and remains stable, stop the gas supply and maintain the pressure, and record the change of the pressure data in the test sealing cavity in real time. Calculate the leakage rate of the sealing component to be measured according to the gas state equation;

[0043] Step Four: Dynamic leakage rate test (optional)

[0044] If it is necessary to measure the dynamic sealing leakage rate of the sealing component to be measured, start the friction motion module during the pressure maintenance stage after stopping the gas supply. Drive the push-pull plate 12 to reciprocate through the reciprocating actuator 7, so that the circular protrusion of the friction plate 9 repeatedly rubs the sealing component to be measured within the range of the anti-leakage seal, realizing the test switching between static leakage rate and dynamic leakage rate.

[0045] Step Five: Influence test under cooling conditions (optional)

[0046] If it is necessary to measure the leakage rate of a single sealing component to be measured under cooling conditions, the water inlet hole and drain hole of the inner sealing component fixture 203 facing away from the end face cooling water channel 2033 can be connected to the cooling water circulation system according to requirements.

[0047] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and can be implemented in other forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent conditions of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claimed rights.

[0048] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A high-temperature airtightness test device for a baseline seal, characterized in that: It includes a machine base (1), a seal fixture group (2), a slide table motion module, and a friction motion module. The machine base (1) has an L-shaped structure on a plane, and its longitudinal area and transverse area respectively carry and assemble the slide table motion module and the friction motion module. The slide table motion module is provided with a slide table (3) capable of longitudinal displacement. The friction motion module horizontally arranges a push-pull plate (12) at the intermediate transfer position of the machine base (1) and controls its displacement through a reciprocating actuator (7). The friction plate (9) is detachably fixed to the front surface of the push-pull plate (12). A circular protrusion is provided at the middle position of the friction plate (9) for contact support of the seal to be tested. The seal fixture group (2) includes an outer seal fixture (201), a middle seal fixture (202), and an inner seal fixture (203) coaxially assembled and fixed from outside to inside. The outer seal fixture (201) is fixed to the end of the slide table (3). A first seal groove (2011) is machined on its front end face and an anti-leakage seal is installed. When the seal fixture group (2) contacts the friction plate (9), the anti-leakage seal is spaced around the circular protrusion to form a test seal cavity. The outer seal fixture (201) is also machined with an exhaust gas discharge hole (2012). A second seal groove (2021) is machined on the front end face of the middle seal fixture (202), and a third seal groove (2031) is machined on the front end face of the inner seal fixture (203). The second seal groove (2021) and the third seal groove (2031) are used to install the seal to be tested. A seal cavity air inlet (2032) is provided on the back end face of the inner seal fixture (203) for connecting the air supply.

2. The high-temperature airtightness test device for a baseline seal according to claim 1, characterized in that: The slide table motion module includes a slide table (3), longitudinal linear guides (4), and an electric cylinder (5). The longitudinal linear guides (4) are fixedly arranged in parallel on both sides of the longitudinal area of the machine base (1). The slide table (3) consists of a slide table body (301) and two wing plates (302). The slide table body (301) is a cylindrical structure and is longitudinally arranged between the longitudinal linear guides (4). The two wing plates (302) are fixedly arranged on both sides of the outer wall of the slide table body (301) and are slidably connected to the longitudinal linear guides (4). The electric cylinder (5) is arranged at the bottom of the slide table (3) and is fixedly connected to the machine base (1). The telescopic end of the electric cylinder (5) is fixedly connected to the bottom of the slide table body (301).

3. The high-temperature airtightness test device for a baseline seal according to claim 1, characterized in that: The friction motion module includes a reciprocating actuator (7), a tension-compression sensor (8), a transverse linear guide (11), and a push-pull plate (12). The transverse linear guide (11) is fixedly arranged in parallel up and down at the intermediate transfer position of the machine base (1). The back surface of the push-pull plate (12) is slidably connected to the transverse linear guide (11). The reciprocating actuator (7) is arranged in the transverse area of the machine base (1) to control the push-pull plate (12) to make reciprocating displacement along the transverse linear guide (11). The tension-compression sensor (8) is arranged at the connection between the reciprocating actuator (7) and the push-pull plate (12).

4. The high-temperature airtightness test device for a baseline seal according to claim 3, characterized in that: The reciprocating actuator (7) includes a driving motor (701), a runner (702), a crank connecting rod (703), and a linear bearing (704). The driving motor (701) is fixedly connected to the machine base (1). The runner (702) is coaxially fixed to the output shaft of the driving motor (701). The linear bearing (704) is fixedly connected to the machine base (1) and is provided with a joint pull rod. One end of the joint pull rod is connected to the side of the push-pull plate (12) through a tension and compression sensor (8). Both ends of the crank connecting rod (703) are hinged to the other end of the joint pull rod and the eccentric shaft provided on the runner (702).

5. The high-temperature airtightness test device for a baseline seal according to claim 1, characterized in that: In the third sealing groove (2031) of the inner layer seal fixture (203), gaskets can be provided to accommodate seal specimens of different sizes.

6. The high-temperature airtightness test device for a baseline seal according to claim 1, characterized in that: A cooling water channel (2033) is machined on the side wall of the inner layer seal fixture (203). The cooling water channel (2033) is provided with a water inlet hole and a drain hole that penetrate through the back end face of the inner layer seal fixture (203).

7. A method for testing the high-temperature airtightness of a baseline seal, characterized in that: According to the high-temperature airtightness test device described in claim 1, its test method includes the following steps: Step 1: Installation of the seal specimen to be tested According to the requirements of single-seal leakage test or double-seal leakage test, install the seal specimen to be tested in the third sealing groove (2031) or the second sealing groove (2021) and the third sealing groove (2031) of the seal fixture group (2). Step 2: Construction of the test seal cavity Control the slide (3) with the seal fixture group (2) to move towards the friction plate (9) through the slide movement module until the seal specimen to be tested contacts the circular protrusion of the friction plate (9) and reaches a predetermined compression amount. At the same time, the anti-leakage seals installed in the first sealing groove (2011) are in spaced contact around the circular protrusion of the friction plate (9) to form a test seal cavity. Step 3: Gas injection and experimental analysis Inject high-temperature and high-pressure gas with a temperature of 20 - 400 °C and a pressure below 3 Mpa into the test seal cavity through the seal cavity air inlet (2032). Use a temperature sensor and a pressure sensor to collect data. When the pressure in the test seal cavity reaches the preset value and remains stable, stop gas supply and maintain the pressure. For the static leakage amount test, directly record the change in the pressure data in the test seal cavity in real time, and calculate the leakage amount of the seal specimen to be tested based on the gas state equation. For the dynamic leakage amount test, start the friction movement module during the pressure maintenance stage after stopping gas supply, and repeatedly rub the seal specimen to be tested within the range of the anti-leakage seal by the circular protrusion of the friction plate (9).

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