Device and method for testing hydraulic dynamic seal in high-temperature environment
By designing a modular high-temperature environment hydraulic dynamic seal testing device, and adopting the static pressure holding method and pressure detection unit, the problems of complex structure and inaccurate test results of existing devices are solved, and efficient and low-cost seal performance evaluation is achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-29
- Publication Date
- 2026-03-27
AI Technical Summary
Existing dynamic sealing test devices have complex structures, are easily affected by interference, lack reliability and intuitiveness in test results, and are complicated to operate, costly, and difficult to adapt to the testing of seals of different specifications.
A high-temperature environment hydraulic dynamic seal testing device was designed, including a rotary drive mechanism, a heating and insulation chamber, and a testing module. It adopts a modular design and performs dynamic seal performance testing through a static pressure holding method. The movable heating and insulation chamber and pressure detection unit simplify the operation process and can adapt to the testing of sealing rings of different specifications.
It improves the accuracy and repeatability of test results, reduces operational complexity and cost, enhances testing efficiency, adapts to the rapid disassembly and assembly of sealing rings of different specifications, and reduces spare parts costs and maintenance difficulty.
Smart Images
Figure CN121740359A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of sealing test technology, specifically relating to a high-temperature environment hydraulic dynamic seal testing device and testing method. Background Technology
[0002] Seals for rotating shafts are widely used in hydraulic systems, pumps and valves, aerospace, automotive, and construction machinery. Their sealing performance directly affects the equipment's efficiency, service life, and operational safety. Especially under extreme conditions of high temperature, high pressure, and high-speed rotation, seals are prone to failure due to material aging, structural deformation, or wear, leading to leaks, increased energy consumption, and even equipment malfunctions. Therefore, testing their dynamic sealing reliability is crucial.
[0003] Most existing dynamic sealing test devices have complex structures, their system stability is easily affected by interference, the reliability and intuitiveness of the test results are insufficient, and they are limited by fixed structures. When testing seals of different specifications, it is necessary to disassemble and replace multiple parts, or even replace the entire test unit, which is complicated, time-consuming and costly. Summary of the Invention
[0004] The technical problem to be solved by the present invention is to provide a high-temperature environment hydraulic dynamic seal testing device and testing method that avoids interference from multiple factors in complex systems, improves the accuracy and repeatability of test results, is low in cost, has a test structure that can be quickly disassembled and assembled, improves testing efficiency, and is adaptable to testing seals of different specifications.
[0005] This invention provides a high-temperature environment hydraulic hydraulic seal testing device, including a rotary drive mechanism, a heating and insulation chamber, and a testing module. The heating and insulation chamber is movable relative to the rotary drive mechanism and has an openable and closable door and a through hole. The testing module includes a test shaft, a test bushing, and a main housing. One end of the test shaft is detachably fixed to the output end of the rotary drive mechanism, and the other end of the test shaft has a groove for installing a seal ring to be tested. The main housing and the test bushing are disposed inside the heating and insulation chamber. The main housing has an inlet / outlet pipe and an overflow pipe communicating with the interior of the main housing, and one end of the main housing has an opening. One end of the test bushing is detachably fixed to the open end of the main housing to allow communication between the interior of the main housing and the interior of the bushing. The other end of the test bushing extends along the through hole and aligns with the end of the test shaft where the seal ring to be tested is installed to form a sealing pair. The test bushing is also equipped with a pressure detection unit.
[0006] Furthermore, a first flange is provided on one end edge of the test bushing facing the main housing, and a second flange is provided on one end edge of the main housing with an opening. The first flange and the second flange are fixed by bolts so that one end of the test bushing is detachably fixed to the end of the main housing with an opening.
[0007] Furthermore, the main housing is provided through at both ends, with one end forming the opening and the other end having a third flange and an end cap fixed to it by bolts. The inlet / outlet pipe and the overflow pipe are provided on the end cap.
[0008] Furthermore, a pressure measurement interface is provided on one side of the test bushing extending along the through hole, and the pressure detection unit and the pressure measurement interface are detachably fixed.
[0009] Furthermore, the test bushing is provided with a temperature measurement interface on one side of the end extending along the through hole, for detachable connection to the temperature detection unit.
[0010] Furthermore, the heating and insulation box includes an insulation box shell and a heating module. The heating module is located inside the insulation box shell. The insulation box shell is provided with pipe holes for the inlet / outlet pipe and the overflow pipe to extend out. The box has two doors, which are symmetrically arranged on one side of the insulation box shell, and each of the two doors is provided with a notch. The notches on the two doors enclose the through hole.
[0011] Furthermore, fixing plates are provided at the lower ends of both sides of the main shell, and the fixing plates are detachably fixed to the ground inside the insulated box shell by bolts.
[0012] Furthermore, it also includes a platform, on which the rotary drive mechanism is mounted, and a guide rail is slidably connected to the bottom of the heating and insulation box. The guide rail is mounted on the platform so that the heating and insulation box can move relative to the rotary drive mechanism, and a limiter is provided on the guide rail or the heating and insulation box to limit the position of the heating and insulation box after it has moved.
[0013] Furthermore, the rotary drive mechanism includes a servo motor, a coupling, and a connecting shaft. The connecting shaft is rotatably supported by a bearing housing, and one end of the connecting shaft is connected to the rotating shaft of the servo motor through the coupling. The other end of the connecting shaft forms the output end of the rotary drive mechanism. The other end of the connecting shaft is detachably fixed to the end of the test shaft away from the test shaft sleeve by bolts.
[0014] The present invention also provides a method for testing hydraulic dynamic seals in a high-temperature environment, using the high-temperature hydraulic dynamic seal testing device described above. The testing method includes the following steps: S1. Place the seal ring to be tested in the groove, and align the end of the test bushing extending along the through hole with the end of the test shaft where the seal ring to be tested is installed to form a sealing pair. S2. Inject liquid into the main housing through the inlet and outlet pipes until liquid flows out of the overflow pipe; S3. Heat the material to the appropriate temperature using a heating and insulation box, and record the initial pressure P1 measured by the pressure detection unit. S4. Drive the test shaft to rotate through the rotary drive mechanism to simulate dynamic working conditions. During or after the dynamic test, record the real-time pressure P2 measured by the pressure detection unit and calculate the pressure drop ΔP=P1-P2 to evaluate the dynamic sealing performance of the seal ring under test.
[0015] The beneficial effects of this invention are that the heating and insulation chamber can provide a stable and uniform high-temperature environment, simulating the working state of the seal under test under high-temperature conditions, providing reliable test conditions for evaluating the temperature resistance, thermal expansion adaptability, and other performance characteristics of sealing materials. The main housing, test bushing, and test shaft end face enclose a closed test chamber. Dynamic sealing performance is tested using the static pressure holding method. Sealing performance can be intuitively and reliably evaluated by monitoring the change of a single pressure parameter (pressure detection unit), avoiding interference from multiple factors in complex systems, improving the accuracy and repeatability of test results, and simplifying the testing operation. The test shaft and test bushing adopt a paired modular design, which, combined with the movable heating and insulation chamber, facilitates quick assembly and disassembly of the test structure, improving testing efficiency. By changing different specifications of bushing combinations, different specifications of sealing rings can be tested, reducing spare parts costs and maintenance difficulty. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the high-temperature environment hydraulic dynamic seal testing device of the present invention.
[0017] Figure 2 This is a longitudinal sectional view of the high-temperature environment hydraulic dynamic seal testing device of the present invention.
[0018] Figure 3 This is a schematic diagram of the rotary drive mechanism of the present invention.
[0019] Figure 4 This is a schematic diagram of the test module of the present invention.
[0020] Figure 5 This is a longitudinal cross-sectional view of the test module of the present invention.
[0021] Figure 6 This is a schematic diagram of the heating and insulation box of the present invention.
[0022] Figure 7 This is a longitudinal sectional view of the heating and insulation box of the present invention.
[0023] In the diagram: 1. Stand; 2. Rotary drive mechanism; 21. Servo motor; 22. Coupling; 23. Connecting shaft; 24. Bearing seat; 3. Test module; 31. Test shaft; 32. Test bushing; 321. First flange; 322. Pressure measurement interface; 323. Temperature measurement interface; 33. Main housing; 331. Second flange; 332. Third flange; 333. Fixing plate; 34. End cover; 4. Heating and insulation box; 41. Insulation box housing; 42. Heating module; 43. Box door; 44. Through hole; 45. Pipe hole; 5. Inlet and outlet pipes; 6. Overflow pipe; 7. Guide rail; 8. Limiting component; 9. Sealing ring to be tested. Detailed Implementation
[0024] like Figures 1-7 As shown, this invention provides a high-temperature environment hydraulic hydraulic seal testing device, including a rotary drive mechanism 2, a heating and insulation chamber 4, and a testing module 3. The heating and insulation chamber 4 is movable relative to the rotary drive mechanism 2, that is, the distance between the heating and insulation chamber 4 and the rotary drive mechanism 2 can be changed by moving the heating and insulation chamber 4. The heating and insulation chamber 4 is provided with an openable and closable chamber door 43 and a through hole 44. The testing module 3 includes a test shaft 31, a test bushing 32, and a main housing 33. One end of the test shaft 31 is detachably fixed to the output end of the rotary drive mechanism 2, and the other end of the test shaft 31 is provided with a groove for installing the sealing ring 9 to be tested. The main housing 33 and the test bushing 32 are disposed inside the heating and insulation chamber 4. The main housing 33 is provided with an inlet / outlet pipe 5 and an overflow pipe 6, which are connected to the interior of the main housing 33. The overflow pipe 6 is positioned higher than the inlet / outlet pipe 5. The overflow pipe 6 is specifically connected to the top area inside the main housing 33, and the inlet / outlet pipe 5 is specifically connected to the bottom area inside the main housing 33. One end of the main housing 33 has an opening, and one end of the test bushing 32 is detachably fixed to the open end of the main housing 33, so that the interior of the main housing 33 communicates with the interior of the bushing. The other end of the test bushing 32 extends through the through hole 44 and aligns with the end of the test shaft 31 where the sealing ring 9 to be tested is installed, forming a sealing pair. A test cavity is formed between the interior of the main housing 33, the interior of the bushing, and the end face of the test shaft 31. A pressure detection unit is provided on the test bushing 32.
[0025] The high-temperature environment hydraulic dynamic seal testing device provided by this invention utilizes a heating and insulation chamber 4 to provide a stable and uniform high-temperature environment, simulating the working state of the seal under test under high-temperature conditions. This provides reliable test conditions for evaluating the temperature resistance, thermal expansion adaptability, and other performance characteristics of the sealing material. The main housing 33, test bushing 32, and the end face of the test shaft 31 form a closed test chamber. Dynamic seal performance is tested using the static pressure holding method. By monitoring the change of a single pressure parameter (pressure detection unit), the sealing performance can be evaluated intuitively and reliably, avoiding interference from multiple factors in complex systems, improving the accuracy and repeatability of test results, and simplifying the testing operation. The test shaft 31 and test bushing 32 adopt a paired modular design. Combined with the movable heating and insulation chamber 4, this facilitates quick assembly and disassembly of the test structure, improving testing efficiency. By changing different bushing combinations, different specifications of sealing rings can be tested, reducing spare parts costs and maintenance difficulty.
[0026] The inner diameter of the test bushing 32 is smaller than the inner diameter of the main housing 33. A first flange 321 is provided on the edge of the test bushing 32 facing the main housing 33, and a second flange 331 is provided on the edge of the main housing 33 with an opening. The first flange 321 and the second flange 331 are fixed with bolts, allowing one end of the test bushing 32 to be detachably fixed to the open end of the main housing 33. This detachable connection method ensures the rigidity and reliability of the connection between the test bushing 32 and the main housing 33, and facilitates disassembly and assembly, making it better suited for scenarios involving frequent changes in test specifications. Further preferably, a first sealing element is provided between the first flange 321 and the second flange 331 to improve the sealing performance after the test bushing 32 and the main housing 33 are connected.
[0027] The main housing 33 is through-connected at both ends, with one end forming the opening and the other end having a third flange 332. The third flange 332 is detachably fixed to the end cap 34 by bolts, thus sealing the other end of the main housing 33. The inlet / outlet pipe 5 and the overflow pipe 6 are specifically mounted on the end cap 34. This split-type arrangement is more rational, facilitating the installation of the inlet / outlet pipe 5 and the overflow pipe 6, and also facilitating cleaning of the inside of the main housing 33. The end of the inlet / outlet pipe 5 furthest from the end cap 34 has an inlet port and an outlet port. The inlet port allows liquid to enter the main housing 33, and the outlet port allows liquid to exit the main housing 33 after testing. Valves are provided on the inlet port, outlet port, and overflow pipe 6.
[0028] A pressure measurement interface 322 is provided on one side of the test bushing 32 extending along the through hole 44. The pressure detection unit and the pressure measurement interface 322 are detachably fixed. The pressure measurement interface 322 is located in the area outside the heating and insulation chamber 4 of the test bushing 32, allowing the pressure detection unit to be installed and calibrated at room temperature, avoiding the impact of high temperature on its accuracy and lifespan, while facilitating real-time monitoring and data acquisition. The pressure detection unit can be a pressure gauge or a pressure sensor.
[0029] The test bushing 32 also has a temperature measurement interface 323 on one side extending from the through hole 44, for detachable connection of a temperature detection unit. Based on this configuration, the temperature of the liquid inside the test chamber can be monitored via the temperature detection unit, providing temperature data support for the analysis of sealing performance under high-temperature conditions. Furthermore, placing the temperature measurement interface 323 in the area of the test bushing 32 outside the heating and insulation chamber 4 allows the temperature detection unit to be installed and calibrated at room temperature, avoiding the impact of high temperatures on its accuracy and lifespan.
[0030] The heating and insulation chamber 4 includes an insulation chamber shell 41 and a heating module 42. The heating module 42 is located inside the insulation chamber shell 41 and can be a quartz lamp or other heating element. The insulation chamber shell 41 has pipe holes 45 for the inlet / outlet pipes 5 and overflow pipes 6 to extend out. There are two chamber doors 43, symmetrically hinged to one side of the insulation chamber shell 41, each with a notch. The notches of the two doors 43 together form a through hole 44. This arrangement allows for both opening of the chamber doors 43 and easy passage of the test bushing 32 through the through hole 44, facilitating the installation and debugging of test components and improving the flexibility of the equipment. Insulation material can be installed on the side wall of the through hole 44 to increase insulation performance.
[0031] The lower ends of both sides of the main housing 33 are provided with fixing plates 333. The fixing plates 333 are detachably fixed to the ground inside the insulation box housing 41 by bolts to ensure the stability of the test module 3 during the test and avoid positional displacement caused by rotational movement, which would affect the test accuracy.
[0032] The invention also includes a test stand 1, on which the rotary drive mechanism 2 is mounted. A guide rail 7 is slidably connected to the bottom of the heating and insulation box 4 via a slider. The guide rail 7 is mounted on the test stand 1 to allow the heating and insulation box 4 to move relative to the rotary drive mechanism 2. A limiting element 8 is provided on the guide rail 7 or the heating and insulation box 4 to limit its position after movement. Based on this configuration, since the relative position of the guide rail 7 and the rotary drive mechanism 2 is fixed, and based on the aforementioned configuration, the movement of the heating and insulation box 4, after its overall movement, eliminates the need for tedious centering adjustments, improving the docking efficiency between the test bushing 32 and the test shaft 31, thereby improving testing efficiency. Furthermore, after the heating and insulation box 4 has moved into position, the limiting element 8 can restrict its position, preventing it from moving relative to the guide rail 7 during testing, thus improving testing reliability. The limiting member 8 can be installed on the side of the heating and insulation box 4 and span the guide rail 7. A bolt is provided on the limiting member 8. After the heating and insulation box 4 is moved into position, the bolt is tightened so that its end abuts against the surface of the guide rail 7 or the platform 1, thereby limiting the position of the heating and insulation box 4. In other embodiments, the limiting member 8 can also adopt other locking structures.
[0033] The rotary drive mechanism 2 includes a servo motor 21, a coupling 22, and a connecting shaft 23. The connecting shaft 23 is rotatably supported by a bearing housing 24, and one end of the connecting shaft 23 is connected to the rotating shaft of the servo motor 21 via the coupling 22. The other end of the connecting shaft 23 forms the output end of the rotary drive mechanism 2. This other end of the connecting shaft 23 is detachably fixed to the end of the test shaft 31 that is away from the test shaft 31 sleeve by bolts. By using the servo motor 21 in combination with the coupling 22 and the connecting shaft 23, precise control of speed and direction of rotation can be achieved, simulating dynamic sealing scenarios in actual working conditions. The connecting shaft 23 is bolted to the test shaft 31, facilitating reliable power transmission and ensuring the ease of replacement of the test shaft 31.
[0034] This invention also provides a method for testing hydraulic dynamic seals in high-temperature environments, using the high-temperature hydraulic dynamic seal testing device described above. The testing method includes the following steps: S1. Place the seal ring 9 to be tested in the groove, and make the end of the test bushing 32 extending along the through hole 44 connect with the end of the test shaft 31 where the seal ring 9 to be tested is installed to form a sealing pair; restrict the position of the heating and heat preservation box 4, install the pressure detection unit to the pressure measurement interface 322, and install the temperature detection unit to the temperature measurement interface 323; S2. Close the valve on the liquid outlet port, inject liquid into the main housing 33 through the liquid inlet port along the liquid inlet and liquid outlet pipes 5 until liquid flows out of the overflow pipe 6, and then close the valve on the liquid inlet port and the overflow pipe 6. S3. Heating is performed through the heating and insulation box 4. When the temperature detection unit detects that the liquid temperature has risen to the corresponding temperature, the heating and insulation box 4 is used to maintain the current temperature, and the initial pressure P1 measured by the pressure detection unit is recorded. S4. Drive the test shaft 31 to rotate through the rotary drive mechanism 2 to simulate dynamic working conditions. During or after the dynamic test, record the real-time pressure P2 measured by the pressure detection unit and calculate the pressure drop ΔP=P1-P2 to evaluate the dynamic sealing performance of the seal ring 9 under test.
[0035] Specifically, the dynamic sealing performance of the tested sealing ring 9 can be evaluated using qualitative or quantitative methods, depending on actual needs. After the test, open the valve on the liquid outlet to drain the liquid.
[0036] This high-temperature environment hydraulic dynamic seal testing method, utilizing the aforementioned high-temperature environment hydraulic dynamic seal testing device, tests dynamic seal performance through a static pressure holding method. By monitoring the change of a single pressure parameter—the pressure detection unit—seal performance can be evaluated intuitively and reliably, avoiding interference from multiple factors in complex systems. This improves the accuracy and repeatability of test results and simplifies operation. The test structure allows for faster assembly and disassembly, increasing testing efficiency. By changing different bushing combinations, it can accommodate different sizes of sealing rings, reducing spare parts costs and maintenance difficulty.
[0037] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of protection of this application is limited to these examples; within the framework of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of one or more embodiments of this application as described above, which are not provided in detail for the sake of brevity.
[0038] One or more embodiments in this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of this application. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of one or more embodiments in this application should be included within the protection scope of this application.
Claims
1. A high-temperature environment hydraulic dynamic seal testing device, characterized in that, The system includes a rotary drive mechanism (2), a heating and insulation box (4), and a test module (3). The heating and insulation box (4) is movable relative to the rotary drive mechanism (2), and is provided with an openable door (43) and a through hole (44). The test module (3) includes a test shaft (31), a test bushing (32), and a main housing (33). One end of the test shaft (31) is detachably fixed to the output end of the rotary drive mechanism (2), and the other end of the test shaft (31) is provided with a groove for installing the sealing ring (9) to be tested. The main housing (33) and the test bushing (32) are connected to the test module (33). 32) Set inside the heating and insulation box (4), the main shell (33) is provided with an inlet / outlet pipe (5) and an overflow pipe (6) that connect the inside of the main shell (33), and one end of the main shell (33) is provided with an opening. One end of the test bushing (32) is detachably fixed to the end of the main shell (33) with the opening, so that the inside of the main shell (33) is connected to the inside of the bushing. The other end of the test bushing (32) extends out along the through hole (44) and is connected to the end of the test shaft (31) where the sealing ring (9) to be tested is installed, so as to form a sealing pair. A pressure detection unit is provided on the test bushing (32).
2. The high-temperature environment hydraulic dynamic seal testing device as described in claim 1, characterized in that, The test bushing (32) is provided with a first flange (321) at one end edge facing the main housing (33), and the main housing (33) is provided with a second flange (331) at one end edge with an opening. The first flange (321) and the second flange (331) are fixed by bolts so that one end of the test bushing (32) is detachably fixed to the end of the main housing (33) with an opening.
3. The high-temperature environment hydraulic dynamic seal testing device as described in claim 2, characterized in that, The main housing (33) is provided through both ends, with one end forming the opening and the other end having a third flange (332) and an end cap (34) fixed by bolts. The inlet / outlet pipe (5) and the overflow pipe (6) are provided on the end cap (34).
4. The high-temperature environment hydraulic dynamic seal testing device as described in any one of claims 1-3, characterized in that, The test bushing (32) has a pressure measurement interface (322) on one side of the end extending along the through hole (44), and the pressure detection unit and the pressure measurement interface (322) are detachably fixed.
5. The high-temperature environment hydraulic dynamic seal testing device as described in claim 4, characterized in that, The test bushing (32) is also provided with a temperature measurement interface (323) on one side of the end extending along the through hole (44) for detachable connection of the temperature detection unit.
6. The high-temperature environment hydraulic dynamic seal testing device as described in any one of claims 1-3 and 5, characterized in that, The heating and insulation box (4) includes an insulation box shell (41) and a heating module (42). The heating module (42) is located inside the insulation box shell (41). The insulation box shell (41) is provided with a pipe hole (45) for the inlet and outlet pipe (5) and the overflow pipe (6) to extend out. There are two boxes (43), which are symmetrically arranged on one side of the insulation box shell (41). Each of the two boxes (43) is provided with a notch. The notches on the two boxes (43) enclose the through hole (44).
7. The high-temperature environment hydraulic dynamic seal testing device as described in claim 6, characterized in that, The lower ends of both sides of the main shell (33) are provided with fixing plates (333), and the fixing plates (333) are detachably fixed to the ground inside the heat preservation box shell (41) by bolts.
8. The high-temperature environment hydraulic dynamic seal testing device as described in any one of claims 1-3, 5, and 7, characterized in that, It also includes a stand (1), the rotary drive mechanism (2) is mounted on the stand (1), and the bottom of the heating and heat preservation box (4) is slidably connected to a guide rail (7). The guide rail (7) is mounted on the stand (1) so that the heating and heat preservation box (4) can move relative to the rotary drive mechanism (2). A limiter (8) is provided on the guide rail (7) or the heating and heat preservation box (4) to limit the position of the heating and heat preservation box (4) after it moves.
9. The high-temperature environment hydraulic dynamic seal testing device as described in any one of claims 1-3, 5, and 7, characterized in that, The rotary drive mechanism (2) includes a servo motor (21), a coupling (22) and a connecting shaft (23). The connecting shaft (23) is rotatably supported by a bearing seat (24). One end of the connecting shaft (23) is connected to the shaft of the servo motor (21) through the coupling (22). The other end of the connecting shaft (23) forms the output end of the rotary drive mechanism (2). The other end of the connecting shaft (23) is detachably fixed to the end of the test shaft (31) away from the test shaft (31) sleeve by bolts.
10. A method for testing hydraulic dynamic seals in a high-temperature environment, characterized in that, The high-temperature environment hydraulic dynamic seal testing device as described in any one of claims 1-9 is used, and the testing method includes the following steps: S1. Place the seal ring (9) to be tested in the groove, and make the end of the test bushing (32) extending along the through hole (44) connect with the end of the test shaft (31) where the seal ring (9) to be tested is installed to form a sealing pair; S2. Inject liquid into the main housing (33) through the inlet / outlet pipe (5) until liquid flows out of the overflow pipe (6); S3. Heat the product to the corresponding temperature using a heating and insulation box (4), and record the initial pressure P1 measured by the pressure detection unit. S4. Drive the test shaft (31) to rotate by the rotary drive mechanism (2) to simulate dynamic working conditions. During or after the dynamic test, record the real-time pressure P2 measured by the pressure detection unit and calculate the pressure drop ΔP=P1-P2 to evaluate the dynamic sealing performance of the seal ring (9) to be tested.