Device and method for testing sealing performance of refrigerant transmission sealing element of superconducting motor

Abstract

The invention discloses a sealing performance test device and method for a superconducting motor refrigerant transmission sealing member, the test device comprises an inner cavity assembly, an outer cavity assembly and a plugging member, one end of the inner cavity assembly is provided with a first air vent, the other end is provided with a movable interface, and an inner radial spigot is formed on the outer wall of the inner cavity assembly at one end of the movable interface; the outer cavity assembly is coaxially arranged in the inner cavity assembly, one end, close to the movable connector, of the outer cavity assembly is provided with a second air vent, an outer radial spigot corresponding to the inner radial spigot is formed in the inner wall of the outer cavity assembly, and an inner ring and an outer ring of the sealing element to be tested are connected to the inner radial spigot and the outer radial spigot in a sealed mode respectively. Pressure measuring ports are formed in the outer wall, on two sides of the sealing element, of the outer cavity assembly, and an exhaust port is formed in the outer wall close to one side of the first ventilation port; the plugging piece is detachably arranged at the movable connector. The technical problems that an existing refrigerant transmission sealing performance testing device for the superconducting motor is too long in cooling time and complex in debugging process are solved.

Description

Technical Field

[0001] The invention relates to the technical field of superconducting motors, and in particular to a sealing performance test device and method for a superconducting motor refrigerant transmission seal. Background Art

[0002] In a superconducting motor, the refrigerant transmission device is a transition device between the stationary refrigerator and the rotor, used to transmit the refrigerant from the stationary refrigerator integrated device to the rotating rotor. The refrigerant transmission device must have good sealing, high transmission efficiency, high pressure resistance and low heat leakage. The performance of the refrigerant transmission device directly affects the overall performance of the superconducting motor. It is a key device of the high-temperature superconducting motor. Therefore, in order to design and manufacture a high-performance refrigerant transmission device, a test device for accurately measuring the sealing performance of its sealing components is essential.

[0003] In order to measure its sealing performance, a test device for measuring leakage rate at low temperature is currently designed, such as the Chinese invention patent application "A transmission performance measurement device and method for a refrigerant transmission component for a superconducting motor" published with publication number CN112649041A. However, the above technology uses an indirect test by heating method, which includes a relatively complex measurement and calculation process, and has the disadvantages of too long test cooling time, complex debugging process, and single measurement object, which leads to a long design verification cycle and affects the overall design progress of the superconducting motor. Summary of the invention

[0004] In order to overcome the above-mentioned deficiencies in the prior art, the present invention proposes a sealing performance test device and method for a superconducting motor refrigerant transmission seal, so as to solve the technical problems of the existing superconducting motor refrigerant transmission sealing performance test device such as long cooling time, complicated debugging process and low precision.

[0005] In order to achieve the above technical objectives, the present invention adopts the following technical solutions: In a first aspect, the present invention provides a sealing performance test device for a superconducting motor refrigerant transmission seal, comprising: An inner cavity component has a first vent at one end and a movable interface at the other end, and an inner radial stop is formed on the outer wall of the inner cavity component at one end of the movable interface; An outer cavity component is coaxially arranged in the inner cavity component, the outer cavity component has a second vent at one end close to the movable interface, an outer radial stop corresponding to the inner radial stop is formed on the inner wall of the outer cavity component, the inner ring and the outer ring of the seal to be tested are respectively sealed and connected to the inner radial stop and the outer radial stop, the outer wall of the outer cavity component on both sides of the seal is formed with pressure measuring ports, and the outer wall close to the first vent is formed with an exhaust port; A blocking piece is detachably arranged at the movable interface.

[0006] In some embodiments, the inner cavity component includes an inner shaft and an inner shaft fixing member. The inner shaft is arranged in the outer cavity component and fixed to the outer cavity component through the inner shaft fixing member fixed to one end of the inner shaft. A first ventilation cavity is formed inside the inner shaft. The first ventilation port and the movable interface are respectively opened at two ends of the first ventilation cavity. The inner radial stop is arranged on the outer wall of one end of the inner shaft where the movable interface is opened.

[0007] In some embodiments, the inner cavity component further includes an inner shaft connecting tube, one end of which is connected to the first air vent, and the other end of which is connected to an external air supply device.

[0008] In some embodiments, the blocking member is bolted to the movable interface.

[0009] In some embodiments, the outer cavity assembly includes an outer shaft and an outer shaft fixing member, a second ventilation cavity is formed inside the outer shaft, the inner shaft is arranged in the second ventilation cavity, the outer shaft fixing member is fixed to one end of the outer shaft, the outer shaft is coaxially connected to the inner shaft fixing member through the outer shaft fixing member, and the second vent, the pressure measuring port and the exhaust port are all opened on the outer shaft.

[0010] In some embodiments, the outer cavity assembly further includes an outer shaft connecting tube, one end of which is connected to the second air vent, and the other end of which is connected to an external air supply device.

[0011] In some embodiments, the seal includes an inner seal and an outer seal that match each other, the inner seal is interference fit with the inner cavity component through the inner radial stop, and the outer seal is interference fit with the outer cavity component through the outer radial stop.

[0012] In some embodiments, a differential pressure measuring instrument is also included, and two interfaces of the differential pressure measuring instrument are respectively connected to the two pressure measuring ports.

[0013] In some embodiments, a gas flow meter is further included, and the gas flow meter is respectively disposed at the exhaust port and the first vent.

[0014] In a second aspect, the present invention provides a sealing performance test method for a superconducting motor refrigerant transmission seal, which is implemented based on the sealing performance test device for a superconducting motor refrigerant transmission seal provided in the first aspect of the present invention. The test method includes a pressure drop test process and a leakage test process, wherein: The pressure drop test process includes: Install the plugging piece at the movable interface; Passing normal temperature gas into the interior of the outer cavity component through the second vent; The pressure drop performance of the seal is evaluated by measuring the pressure difference at two pressure taps; The leakage test process includes: Remove the plugging piece from the movable interface and plug the two pressure measuring ports; Introducing normal temperature gas into the inner cavity component through the first vent; The leakage performance of the seal is evaluated by measuring the gas flow rate flowing through the first vent and the exhaust port.

[0015] Compared with the prior art, the present invention provides a sealing performance test device and method for a superconducting motor refrigerant transmission seal, which can perform a pressure drop test on the seal under the condition that the interior of the inner cavity component is sealed by a sealing member, and perform a leakage test under the condition that the seal on the interior of the inner cavity component is opened by removing the sealing member and the pressure measuring port is sealed at the same time. The test device of the present invention has both pressure drop test and leakage test modes through clever structural design, and has the advantages of simple structure and easy processing and manufacturing. The test process is simple and accurate, which can greatly shorten the design cycle of the superconducting motor refrigerant transmission device and improve the design accuracy, and plays an important auxiliary role in the design and manufacture of superconducting motors. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of the test device of the present invention; Figure 2 is an exploded view of the test device of the present invention; Figure 3 is a gas flow diagram of the test device of the present invention during a pressure drop test; Figure 4 is a gas flow diagram of the test device of the present invention during a leakage test; Figure 5 It is a flow chart of the test method of the present invention.

[0017] The following are the descriptions of the reference numerals: 100, inner cavity component, 101, first vent, 102, movable interface, 110, inner shaft, 111, first vent cavity, 120, inner shaft fixing member, 130, inner shaft connecting pipe; 200, outer cavity assembly, 201, second vent, 202, pressure measuring port, 203, exhaust port, 210, outer shaft, 211, second vent cavity, 220, outer shaft fixing member, 230, outer shaft connecting pipe; 300, blocking parts; 400, seal, 410, inner seal, 420, outer seal. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0019] In view of the technical problems of long cooling time, complicated debugging process and low precision in the existing sealing performance test equipment for superconducting motor refrigerant transmission, the present invention proposes a sealing performance test equipment and method for superconducting motor refrigerant transmission seals. This test equipment can perform a nitrogen (or air) pressure drop test on the seal at room temperature, and then reverse the air inlet and block or open certain channels to perform a nitrogen (or air) leakage test on the seal at room temperature. At the same time, the position for installing the seal is designed with axial and radial positioning, and different seal combinations can be disassembled and replaced, so that the pressure drop and leakage of different seals can be measured.

[0020] See also Figure 1 and Figure 2 As shown, the first aspect of the present invention provides a sealing performance test device for a superconducting motor refrigerant transmission seal, comprising an inner cavity component 100, an outer cavity component 200 and a sealing component 300, wherein the inner cavity component 100 has a first air vent 101 at one end and a movable interface 102 at the other end, an outer wall of the inner cavity component 100 at one end of the movable interface 102 and an inner wall of the outer cavity component 200 at a corresponding position are respectively formed with inner radial stoppers and outer radial stoppers, and an inner ring and an outer ring of the sealing component 400 are respectively sealed and connected to the inner radial stoppers and the outer radial stoppers; an end of the outer cavity component 200 close to the movable interface 102 has a second air vent 201, an outer wall of the outer cavity component 200 located on both sides of the sealing component 400 is formed with a pressure measuring port 202 and an outer wall close to the first air vent 101 is formed with an exhaust port 203; the sealing component 300 is detachably arranged at the movable interface 102.

[0021] In the present invention, when the sealing member 300 seals the internal space of the inner cavity component 100, that is, when the sealing member 300 is installed in the movable interface 102, the sealing performance of the seal 400 can be obtained by passing room temperature gas into the second vent 201 and measuring the pressure difference between the two pressure measuring ports 202. The larger the measured pressure difference value, the worse the sealing performance of the seal 400 and the more gas passes through the seal 400. After the pressure drop test is completed, the sealing member 300 is removed from the movable interface 102 and the two pressure measuring ports 202 are sealed. Then, air is ventilated into the interior of the inner cavity component 100 through the first vent 101. The leakage rate of the seal 400 can be obtained by measuring the gas flow rates of the first vent 101 and the exhaust port 203 and calculating the percentage of the gas flow rate at the exhaust port 203 to the gas flow rate out of the first vent 101, thereby judging the leakage performance of the seal 400. It can be seen that the present invention can carry out two modes of testing with one device, which simplifies the test process, greatly shortens the design period of the superconducting motor refrigerant transmission device and improves the accuracy; and the test device of the present invention has a simple structure and is easy to process and manufacture, which plays an important auxiliary role in the design and manufacture of superconducting motors.

[0022] It can be understood that the present invention uses normal temperature gas measurement to test the sealing performance of the refrigerant transmission device, compares the test results with the simulation results, and corrects the simulation method. Due to the similarity of gas flow characteristics, the same simulation method is also applicable at low temperatures. In the pressure drop test, the present invention uses a detachable structure to compare and select sealing components with better sealing performance, and then changes to a leakage rate test to measure the leakage rate of the selected sealing components, and compares it with the simulation results of different working conditions and corrects the simulation method. After obtaining an accurate simulation calculation method, this method is used to calculate the leakage rate of low-temperature helium in the refrigerant coupling device, and finally the final solution is tested in a low-temperature measurement device to verify the design.

[0023] The components and working principles of the sealing performance test device for superconducting motor refrigerant transmission seals of the present invention are described in detail below.

[0024] In one embodiment, the inner cavity assembly 100 includes an inner shaft 110, an inner shaft fixing member 120 and an inner shaft connecting tube 130. The inner shaft 110 is arranged in the outer cavity assembly 200, specifically in the second ventilation cavity 211 of the outer shaft 210. The inner shaft fixing member 120 is arranged at one end of the inner shaft 110. After the inner shaft 110 is inserted into the second ventilation cavity 211 of the outer shaft 210, it is fixedly connected with the outer shaft fixing member 220 through the inner shaft fixing member 120. A first ventilation cavity 111 is formed inside the inner shaft 110. The first ventilation port 101 and the movable interface 102 are respectively opened at both ends of the first ventilation cavity 111. The inner radial stop is arranged on the outer wall of one end of the inner shaft 110 where the movable interface 102 is opened, and is used to position the inner seal 410 of the seal 400. One end of the inner shaft connecting tube 130 is connected to the first ventilation port 101, and the other end thereof is connected to an external air supply device.

[0025] In one embodiment, the outer cavity assembly 200 includes an outer shaft 210, an outer shaft fixing member 220 and an outer shaft connecting tube 230. A second ventilation cavity 211 is formed inside the outer shaft 210. The inner shaft 110 is disposed in the second ventilation cavity 211. The outer shaft fixing member 220 is fixed to one end of the outer shaft 210. The outer shaft 210 is coaxially connected to the inner shaft fixing member 130 through the outer shaft fixing member 230. The second ventilation port 201 is provided at one end of the outer shaft 210 away from the outer shaft fixing member 220. Two pressure measuring ports 202 are provided on the outer wall of the outer shaft 210 and are located on both sides of the seal 400 for measuring the pressure of the gas on both sides of the seal 400. The exhaust port 203 is provided on the outer wall of the outer shaft 210. One end of the outer shaft connecting tube 230 is connected to the second ventilation port 201, and the other end thereof is connected to an external gas supply device.

[0026] In one embodiment, the inner shaft fixing member 120 and the outer shaft fixing member 220 are flange structures that fit together.

[0027] In one embodiment, the blocking member 300 and the movable interface 102 are detachably connected by bolts.

[0028] In one embodiment, the test device further includes a differential pressure measuring instrument and a gas flow meter, wherein two interfaces of the differential pressure measuring instrument are respectively connected to the two pressure measuring ports 202; the gas flow meter is respectively arranged at the exhaust port 203 and the first vent 101.

[0029] In one embodiment, the seal 400 includes an inner seal 410 and an outer seal 420 that are matched with each other, wherein the inner seal 410 is interference fit with the outer wall of the inner shaft 110 of the inner cavity component 100 through the inner radial stop, and the outer seal 420 is interference fit with the inner wall of the outer periphery 210 of the outer cavity component 200 through the outer radial stop.

[0030] It should be noted that the inner seal 410 represents several sealing structures with the same inner diameter and different outer ring structures, and the outer seal 420 represents several sealing structures with the same outer diameter and different inner ring structures. The outer ring structure and inner ring structure of the inner seal 410 and the outer seal 420 of the same seal 400 are matching structures, and there can be multiple such matching structures. Therefore, the test device of the present invention is capable of measuring the sealing performance of seals 400 with different sealing structure combinations, and has a wider range of applications compared to existing test devices.

[0031] The working principle of the test device provided by the present invention is as follows: 1. Pressure drop test process: like Figure 3 As shown, during the pressure drop test, the plugging member 300 is installed in the movable interface 102, and the pressure measuring port 202 and the exhaust port 203 are in an open state. The two ends of the differential pressure measuring instrument are respectively connected to the two pressure measuring ports 202, and then the room temperature gas is introduced into the second ventilation cavity 211 through the second vent 201. Since the first ventilation cavity 111 is blocked by the plugging member 300, the gas flows to the sealing member 400 around the plugging member 300. At this time, the pressure difference between the gas inside and outside the sealing member 400 can be measured by the differential pressure measuring instrument to evaluate the sealing performance of the sealing member 400. The larger the pressure difference, the poorer the sealing performance of the sealing member 400. 2. Leakage test process: like Figure 4 As shown, during the leakage test, the sealing member 300 is removed from the movable interface 102, and the two pressure measuring ports 202 are blocked at the same time, and then room temperature gas is introduced into the first ventilation cavity 111 through the first ventilation port 101. Since the sealing member 300 is removed, the gas flows from the first ventilation cavity 111 to the second ventilation cavity 211. At this time, the total flow rate of the gas entering the first ventilation cavity 111 and the flow rate of the gas flowing out of the exhaust port 203 are measured by a gas flow meter, and the percentage of the flow rate of the gas flowing out of the exhaust port 203 to the total flow rate of the gas in the first ventilation cavity 111 is calculated, which is the leakage rate of the sealing member 400. The larger the value, the worse the leakage performance of the sealing member 400.

[0032] Second, as Figure 5As shown, the present invention also provides a sealing performance test method for a superconducting motor refrigerant transmission seal, which is implemented based on the sealing performance test device for a superconducting motor refrigerant transmission seal described in the first aspect of the present invention. The test method includes a pressure drop test process and a leakage test process, wherein: The pressure drop test process includes: Install the blocking member 300 at the movable interface 102; A normal temperature gas is introduced into the interior of the outer chamber component 200 through the second vent 201; The pressure drop performance of the seal is evaluated by measuring the pressure difference at the two pressure measuring ports 202; The leakage test process includes: Remove the blocking member 300 from the movable interface 102 and block the two pressure measuring ports 202; A normal temperature gas is introduced into the inner cavity component 100 through the first vent 101; The leakage performance of the seal is evaluated by measuring the gas flow rate flowing through the first vent 101 and the exhaust port 203 .

[0033] In summary, the sealing performance test device and method of a superconducting motor refrigerant transmission seal provided by the present invention, through ingenious structural design, enables one device to simultaneously have two modes of pressure drop test and leakage test, and has the advantages of simple structure and easy processing and manufacturing; and the test process is simple and accurate, which can greatly shorten the design cycle of the superconducting motor refrigerant transmission device and improve the design accuracy, and plays an important auxiliary role in the design and manufacture of superconducting motors.

[0034] The specific implementation of the present invention described above does not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A sealing performance test device for superconducting motor refrigerant transmission seal, characterized in that: include: An inner cavity component has a first vent at one end and a movable interface at the other end, and an inner radial stop is formed on the outer wall of the inner cavity component at one end of the movable interface; An outer cavity component is coaxially arranged in the inner cavity component, the outer cavity component has a second vent at one end close to the movable interface, an outer radial stop corresponding to the inner radial stop is formed on the inner wall of the outer cavity component, the inner ring and the outer ring of the seal to be tested are respectively sealed and connected to the inner radial stop and the outer radial stop, the outer wall of the outer cavity component on both sides of the seal is formed with pressure measuring ports, and the outer wall close to the first vent is formed with an exhaust port; A blocking piece is detachably arranged at the movable interface.

2. The sealing performance test device for superconducting motor refrigerant transmission seal according to claim 1, characterized in that: The inner cavity component includes an inner shaft and an inner shaft fixing part. The inner shaft is arranged in the outer cavity component and is fixed to the outer cavity component through the inner shaft fixing part fixed to one end of the inner shaft. A first ventilation cavity is formed inside the inner shaft. The first ventilation port and the movable interface are respectively opened at two ends of the first ventilation cavity. The inner radial stop is arranged on the outer wall of one end of the inner shaft where the movable interface is opened.

3. The sealing performance test device for superconducting motor refrigerant transmission seal according to claim 2, characterized in that: The inner cavity component also includes an inner shaft connecting tube, one end of which is connected to the first air vent, and the other end of which is connected to an external air supply device.

4. The sealing performance test device for superconducting motor refrigerant transmission seal according to claim 3, characterized in that: The blocking piece is connected with the movable interface bolts.

5. The sealing performance test device for superconducting motor refrigerant transmission seal according to claim 2, characterized in that: The outer cavity assembly includes an outer shaft and an outer shaft fixing part. A second ventilation cavity is formed inside the outer shaft. The inner shaft is arranged in the second ventilation cavity. The outer shaft fixing part is fixed to one end of the outer shaft. The outer shaft is coaxially connected with the inner shaft fixing part through the outer shaft fixing part. The second ventilation port, the pressure measuring port and the exhaust port are all opened on the outer shaft.

6. The sealing performance test device for superconducting motor refrigerant transmission seal according to claim 5, characterized in that: The outer cavity component also includes an outer shaft connecting tube, one end of which is connected to the second air vent, and the other end of which is connected to an external air supply device.

7. The sealing performance test device for superconducting motor refrigerant transmission seal according to claim 1, characterized in that: The sealing member comprises an inner sealing member and an outer sealing member which are matched with each other. The inner sealing member is interference-fitted with the inner cavity component through the inner radial stopper, and the outer sealing member is interference-fitted with the outer cavity component through the outer radial stopper.

8. The sealing performance test device for superconducting motor refrigerant transmission seal according to claim 1, characterized in that: It also includes a differential pressure measuring instrument, wherein two interfaces of the differential pressure measuring instrument are respectively connected to the two pressure measuring ports.

9. The sealing performance test device for superconducting motor refrigerant transmission seal according to claim 1, characterized in that: It also includes a gas flow meter, which is respectively arranged at the exhaust port and the first vent.

10. A method for testing the sealing performance of a superconducting motor refrigerant transmission seal, characterized in that: The sealing performance test device for superconducting motor refrigerant transmission seal according to any one of claims 1 to 9 is implemented, wherein the test method includes a pressure drop test process and a leakage test process, wherein: The pressure drop test process includes: Install the plugging piece at the movable interface; Passing normal temperature gas into the interior of the outer cavity assembly through the second vent; The pressure drop performance of the seal is evaluated by measuring the pressure difference at two pressure taps; The leakage test process includes: Remove the plugging piece from the movable interface and plug the two pressure measuring ports; Introducing normal temperature gas into the inner cavity component through the first vent; The leakage performance of the seal is evaluated by measuring the gas flow rate flowing through the first vent and the exhaust port.

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