A tool for spring energy storage sealing ring reciprocating leakage test

Abstract

The utility model discloses a kind of tool for spring energy storage sealing ring reciprocating leakage test, including tool base, cover, transmission rod and lower valve stem, test gas channel is opened in the inside of tool base, blind hole is opened in the top of tool base, the cover inner cavity of cover is connected with test gas channel by blind hole, valve core is pressed in the inner bottom of blind hole using pressing block, the bottom end of lower valve stem can be inserted into test gas channel by passing through valve core, to form sealing groove using lower valve stem, valve core and blind hole between, spring energy storage sealing ring is nested on the bottom end of lower valve stem and located in sealing groove, using its block the passage between test gas channel and cover inner cavity, transmission rod one end is inserted into pressing block after passing through the top of cover and is cooperated with the top end of lower valve stem transmission connection, by the action of transmission rod, lower valve stem can be driven to reciprocate along upper and lower directions;Leakage measuring port is also opened on cover, when testing, using leakage measuring port to test the sealing performance of spring energy storage sealing ring.

Description

Technical Field

[0001] This utility model relates to a sealing ring testing fixture, and more particularly to a fixture for reciprocating leakage testing of spring energy storage sealing rings, belonging to the field of sealing ring performance testing technology. Background Technology

[0002] Spring energy storage seals consist of a high-performance polymer shell and a stainless steel energy storage spring. They are high-efficiency sealing elements that rely on the built-in spring to provide preload and an elastomer (such as rubber or PTFE) to achieve a seal. The core feature is "spring energy storage + elastomer fit". They are suitable for rotating, reciprocating and static sealing applications and are often used to prevent gas or liquid leakage. They are widely used in mechanical, hydraulic and aerospace equipment.

[0003] When spring-loaded energy storage seals are used on the valve stem of a gas valve, the valve stem is a reciprocating component. Therefore, the spring-loaded energy storage seal must achieve dynamic sealing to prevent internal and external gas leakage, which places extremely high safety requirements on the seal. For this reason, before the spring-loaded energy storage seal leaves the factory, its sealing performance needs to be tested under the conditions of reciprocating motion of the gas valve stem.

[0004] A search revealed no existing patent documents that are identical or similar to this application.

[0005] In summary, designing a fixture for reciprocating leakage testing of spring energy storage seals, capable of simulating reciprocating motion scenarios to test gas leakage in the spring energy storage seals, thereby ensuring the sealing performance of the spring energy storage seals and improving the safety of equipment in daily use, is an urgent technical problem to be solved. Utility Model Content

[0006] The technical problem to be solved by this utility model is to address the deficiencies in the existing technology by providing a tooling for reciprocating leakage testing of spring energy storage seals. This tooling can simulate the gas leakage test of spring energy storage seals in reciprocating motion scenarios, thereby ensuring the sealing performance of spring energy storage seal products and improving the safety of equipment in daily use.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows: a fixture for reciprocating leakage testing of a spring energy storage sealing ring, comprising a fixture base, a cover, a transmission rod, and a lower valve rod. A test air passage is opened inside the fixture base, and a blind hole is opened at the top of the fixture base. The cover is tightly fitted onto the top of the fixture base, and the inner cavity of the cover is connected to the test air passage through the blind hole. A pressure block and a valve core are installed inside the blind hole. The pressure block presses the valve core tightly against the bottom of the blind hole. The lower valve rod is located inside the pressure block, and the bottom end of the lower valve rod passes through the valve core and can extend into the test air passage, thereby utilizing the lower valve rod and valve... A sealing groove is formed between the core and the blind hole. The spring energy storage sealing ring under test is fitted onto the bottom end of the lower valve rod and located within the sealing groove. The spring energy storage sealing ring blocks the passage between the test air channel and the inner cavity of the cover. One end of the transmission rod passes through the top of the cover and extends into the pressure block, where it engages with the top of the lower valve rod for transmission. The movement of the transmission rod drives the lower valve rod to reciprocate in the up and down direction. A leak test port is also provided on the cover. During testing, the leak test port is used to test whether gas can flow from the test air channel along the blind hole into the inner cavity of the cover, thereby testing the sealing performance of the spring energy storage sealing ring.

[0008] Preferably, the blind hole includes an upper hole at the top of the tooling base and a lower hole at the bottom of the upper hole. The inner diameter of the lower hole is smaller than the inner diameter of the upper hole, thus forming a stepped countersunk hole between the upper and lower holes. An internal thread is formed on the inner circumferential surface of the upper hole. The pressure block is a hollow column with an external thread on its outer circumferential surface. The valve core includes a hollow column and a flange on the outer circumferential surface of one end of the column. One end of the valve core column is inserted into the lower hole, and one end face of the valve core flange contacts the bottom of the upper hole. The external thread of the pressure block is then threaded into the internal thread of the upper hole of the blind hole, and the pressure block is tightened into the blind hole. After tightening, the pressure block presses the valve core into the bottom of the blind hole, and a gap H1 is left between the end face of the valve core column and the bottom of the lower hole. The test air passage includes a horizontally arranged inlet air passage, an outlet air passage, and an intermediate air passage disposed between the inlet air passage and the outlet air passage. The inlet air passage is connected to the outlet air passage through the intermediate air passage, and the intermediate air passage is also connected to the bottom end of the lower hole. When the bottom end of the lower valve stem passes through the inner cavity of the valve core column and extends into the intermediate air passage, a sealing groove is formed between the lower valve stem, one end face of the valve core column, and the lower hole of the blind hole.

[0009] Preferably, a locking nut is threaded onto the outer circumferential surface of the pressure block.

[0010] Preferably, the transmission rod includes a rotating shaft and an upper valve rod. One end of the rotating shaft passes through the top of the cover and extends into the inner cavity of the cover, where it is connected to the top of the upper valve rod via a coupling. An external thread is provided on the outer circumferential surface of the upper valve rod, and an internal thread is provided on the inner circumferential surface of the pressure block. The external thread of the rod and the internal thread of the pressure block are threaded together, thereby screwing one end of the upper valve rod into the inner cavity of the pressure block. A T-shaped slot is provided at one end of the upper valve rod, and a T-shaped protrusion is provided at the top of the lower valve rod. The T-shaped protrusion engages with the T-shaped slot, thereby connecting the tops of the upper and lower valve rods.

[0011] Preferably, the other end of the rotating shaft is connected to a power mechanism, which can drive the rotating shaft to rotate.

[0012] Preferably, the power mechanism is a pneumatic actuator with time relay control.

[0013] Preferably, a sealing ring one is provided at one end of the rotating shaft where it passes through the top of the cover, and a sealing ring two can also be provided on the contact surface between the cover and the top of the tooling base.

[0014] Preferably, the intermediate air passage includes an upper intermediate air passage and a lower intermediate air passage connected to the upper intermediate air passage. The inner diameter of the lower intermediate air passage is less than the inner diameter of the upper intermediate air passage, thereby forming a stepped countersunk hole between the upper and lower intermediate air passages. The inlet passage is connected to the lower intermediate air passage, and the outlet passage is connected to the upper intermediate air passage. The bottom end of the lower valve stem is provided as a conical surface. By moving the lower valve stem downward, the conical surface at the bottom end of the lower valve stem contacts the stepped portion of the stepped countersunk hole, which can isolate and block the gas flow between the inlet passage and the outlet passage.

[0015] Preferably, the tooling further includes a cryogenic chamber filled with liquid nitrogen, and the tooling base is placed in the cryogenic chamber with the liquid nitrogen encasing the outside of the tooling base.

[0016] The beneficial effects of this utility model are as follows: Through the above-mentioned structural design, this utility model utilizes the reciprocating motion of the lower valve stem in the up-and-down direction to simulate the actual use scenario of the spring energy storage seal ring, and conducts gas leakage tests on the spring energy storage seal ring, thereby ensuring the sealing performance of the spring energy storage seal ring product and improving the safety of the equipment in daily use conditions. The introduction of a pneumatic actuator and a time relay into the power mechanism completely frees up the testing personnel and avoids the unknown risks caused by seal failure of the test piece; at the same time, a counter is added, making the number of reciprocating movements clearly visible, eliminating the need for manual counting and making the data more reliable. The separate design of the rotating shaft of the test fixture greatly reduces maintenance costs. When the shaft wears, only the damaged part needs to be replaced, while reducing friction greatly increases service life. The addition of a locking nut at the connection significantly improves the reliability of the connection, preventing loosening due to vibration and impact generated during testing, and ensuring the stability and safety of the fixture. By standardizing the design of the test fixture, it can achieve reciprocating motion even at ultra-low temperatures, thus meeting the requirements for reciprocating ultra-low temperature testing of spring energy storage seals. Moreover, the test personnel do not need to operate it manually at all; they only need to perform leak detection on the test piece from the operating table, which greatly improves the safety of the experiment. Attached Figure Description

[0017] Figure 1 A schematic diagram of the axial cross-sectional structure of the tooling in Embodiment 1 of this utility model without the spring energy storage sealing ring; Figure 2 In Example 1, when the spring energy storage seal is not placed, Figure 1 Enlarged structural diagram of section A in the middle; Figure 3 In Example 1, after placing the spring energy storage sealing ring, Figure 1 Enlarged structural diagram of section A in the middle; Figure 4 This is a partial axial cross-sectional view of the tooling base according to Embodiment 1 of this utility model; Figure 5 This is a schematic axial cross-sectional view of the pressure block according to Embodiment 1 of this utility model; Figure 6 This is a schematic axial cross-sectional view of the valve core according to Embodiment 1 of this utility model; Figure 7 This is a partial axial cross-sectional view of the tooling in Embodiment 1 of the present invention when the spring energy storage seal ring is not placed. Figure 8 This is a schematic axial cross-sectional view of the upper valve stem in Embodiment 1 of this utility model; Figure 9 This is a schematic axial cross-sectional view of the lower valve stem according to Embodiment 1 of this utility model. Figure 10 In Example 1, when the lower valve stem is used to quickly isolate and block the gas flow between the intake and exhaust channels, Figure 1 Enlarged structural diagram of section A in the middle; Figure 11 This is a schematic diagram of the axial cross-sectional structure of the tooling in Embodiment 2 of this utility model; In the diagram: 1. Tooling base; 2. Cover; 211. Inner cavity of the cover; 3. Transmission rod; 311. Rotating shaft; 312. Upper valve stem; 313. Coupling; 314. External thread of the rod; 315. T-slot hole; 4. Lower valve stem; 411. T-shaped protrusion; 412. Conical surface; 5. Test air passage; 511. Inlet passage; 512. Outlet passage; 513. Intermediate air passage; 5131. Upper intermediate air passage; 5132. Lower intermediate air passage 5133. Stepped section; 6. Blind hole; 611. Upper hole; 612. Lower hole; 613. Internal thread of upper hole; 7. Pressure block; 711. External thread of pressure block; 712. Internal thread of pressure block; 8. Valve core; 811. Column; 812. Flange; 9. Sealing groove; 10. Spring energy storage sealing ring; 11. Leak test port; 12. Bolt; 13. Locking nut; 14. Sealing ring one; 15. Cryogenic chamber; 16. Liquid nitrogen; 17. Sealing ring two. Detailed Implementation

[0018] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0019] Example 1: As Figures 1 to 3As shown, a fixture for reciprocating leakage testing of a spring energy storage sealing ring includes a fixture base 1, a cover 2, a transmission rod 3, and a lower valve rod 4. A test air passage 5 is formed inside the fixture base 1, and a blind hole 6 is formed at the top of the fixture base 1. The cover 2 is tightly fitted onto the top of the fixture base 1. The inner cavity 211 of the cover 2 is connected to the test air passage 5 through the blind hole 6. A pressure block 7 and a valve core 8 are installed inside the blind hole 6. The pressure block 7 presses the valve core 8 tightly against the bottom of the blind hole 6. The lower valve rod 4 is located inside the pressure block 7, and its bottom end passes through the valve core 8 and extends into the test air passage 5, thereby forming a sealing groove between the lower valve rod 4, the valve core 8, and the blind hole 6. 9. The tested spring energy storage sealing ring 10 is sleeved on the bottom end of the lower valve stem 4 and located within the sealing groove 9. The spring energy storage sealing ring 10 blocks the passage between the test air channel 5 and the inner cavity 211 of the cover body. One end of the transmission rod 3 passes through the top of the cover body 2 and extends into the pressure block 7, engaging with the top end of the lower valve stem 4 for transmission. The movement of the transmission rod 3 drives the lower valve stem 4 to reciprocate in the up-down direction. A leak test port 11 is also provided on the cover body 2. During testing, the leak test port 11 is used to test whether gas can flow from the test air channel 5 into the inner cavity 211 of the cover body 211 through the blind hole 6, thereby testing the sealing performance of the spring energy storage sealing ring 10. This embodiment, through the above structural design, uses the reciprocating motion of the lower valve stem in the up-down direction to simulate the actual use scenario of the spring energy storage sealing ring, conducting a gas leakage test on the spring energy storage sealing ring, thereby ensuring the sealing performance of the spring energy storage sealing ring product and improving the safety of the equipment in daily use conditions. Leak test port 11 can be connected to a special measuring instrument via an external air tube, or only the air tube can be connected externally. Then, the air tube is inserted into the water to see if any bubbles emerge from the air tube inserted into the water. If so, it indicates that there is a gas leak.

[0020] like Figure 4 As shown, the blind hole 6 includes an upper hole 611 located at the top of the tooling base 1 and a lower hole 612 located at the bottom of the upper hole 611. The inner diameter of the lower hole 612 is less than the inner diameter of the upper hole 611, thus forming a stepped countersunk hole between the upper hole 611 and the lower hole 612. An internal thread 613 is formed on the inner circumferential surface of the upper hole 611. Figure 5 As shown, the pressure block 7 is a hollow columnar shape, and an external thread 711 is provided on the outer circumferential surface of the hollow columnar pressure block 7. The outer diameter of the hollow columnar pressure block 7 matches the inner diameter of the upper hole 611. Figure 6 As shown, the valve core 8 includes a hollow column 811 and a flange 812 disposed on the outer circumferential surface of one end of the column 811. The outer diameter of the column 811 matches the inner diameter of the lower hole 612. Figure 2 and Figures 4 to 6As shown, one end of the cylinder 811 of the valve core 8 is inserted into the lower hole 612, and one end face of the flange 812 of the valve core 8 contacts the bottom of the upper hole 611. Then, the external thread 711 of the pressure block 7 is threaded into the internal thread 613 of the upper hole of the blind hole 6, and the pressure block 7 is tightened into the blind hole 6. After tightening, the pressure block 7 presses the valve core 8 against the bottom of the blind hole 6. At this time, a gap H1 is left between one end face of the cylinder 811 of the valve core 8 and the bottom of the lower hole 612. Here, to ensure the tightening of the pressure block 7, as follows... Figure 1 As shown, a locking nut 13 can also be threaded onto the outer circumferential surface of the pressure block 7, and the locking nut 13 can be used to ensure that the pressure block 7 can be tightened in the blind hole 6.

[0021] like Figure 2 and Figure 4 As shown, the test air passage 5 includes a horizontally arranged inlet passage 511, an outlet passage 512, and an intermediate air passage 513 disposed between the inlet passage 511 and the outlet passage 512. The inlet passage 511 is connected to the outlet passage 512 through the intermediate air passage 513, and the intermediate air passage 513 is also connected to the bottom end of the lower hole 612. When the bottom end of the lower valve stem 4 passes through the inner cavity of the column 811 of the valve core 8 and extends into the intermediate air passage 513, a sealing groove 9 for placing the spring energy storage sealing ring 10 is formed between the lower valve stem 4, one end face of the column 811 of the valve core 8, and the lower hole 612 of the blind hole 6.

[0022] like Figure 5 , Figures 7 to 9As shown, the cover 2 is locked to the top of the tooling base 1 by bolts 12. The transmission rod 3 includes a rotating shaft 311 and an upper valve stem 312. One end of the rotating shaft 311 passes through the top of the cover 2 and extends into the inner cavity 211 of the cover, and is connected to the top of the upper valve stem 312 via a coupling 313. Here, a sealing ring 14 is provided at the end of the rotating shaft 311 where it passes through the top of the cover 2, and a sealing ring 17 can also be provided on the contact surface between the cover 2 and the top of the tooling base 1. Both the sealing ring 14 and the sealing ring 17 can be made of NBR rubber O-rings. An external thread 314 is provided on the outer circumferential surface of the upper valve stem 312, and an internal thread 712 is provided on the inner circumferential surface of the pressure block 7. The external thread 314 and the internal thread 712 of the pressure block are threaded together to screw one end of the upper valve stem 312 into the inner cavity of the pressure block 7. A T-shaped slot 315 is provided on one end of the upper valve stem 312, and a T-shaped protrusion 411 is provided on the top end of the lower valve stem 4. The T-shaped protrusion 411 is engaged with the T-shaped slot 315 to connect the top ends of the upper valve stem 312 and the lower valve stem 4. When connected, the T-shaped protrusion 411 is engaged with the upper valve stem 312 from the side to the T-shaped slot 315. After engagement, the upper valve stem 312 and the lower valve stem 4 cannot rotate; they can only move vertically. During testing, the other end of the rotating shaft 311 is connected to the power mechanism. The power mechanism drives the rotating shaft 311 to rotate, which in turn drives the upper valve stem 312 to rotate. Since the upper valve stem 312 is threaded into the pressure block 7, it moves up and down along the inner cavity of the pressure block 7. Due to the T-shaped locking structure between the upper valve stem 312 and the lower valve stem 4, the rotation of the upper valve stem 312 does not drive the lower valve stem 4 to rotate. However, when the upper valve stem 312 moves up and down, it drives the lower valve stem 4 to move down and along the inner cavity of the pressure block 7, thus simulating a reciprocating motion scenario. Here, the power mechanism can be set as a pneumatic actuator with time relay control, such as a cylinder, and the frequency of the cylinder's operation can be controlled by the time relay. This embodiment introduces a pneumatic actuator and a time relay, which completely frees up the hands during testing and avoids the unknown risks caused by the failure of the test piece's seal. At the same time, a counter can be added to the power mechanism to make the number of reciprocating movements clearly visible, eliminating the need for manual counting and making the data more reliable.

[0023] like Figure 4As shown, the intermediate air passage 513 includes an upper intermediate air passage 5131 and a lower intermediate air passage 5132 connected to the upper intermediate air passage 5131. The inner diameter of the lower intermediate air passage 5132 is less than the inner diameter of the upper intermediate air passage 5131, thus forming a stepped countersunk hole between the upper intermediate air passage 5131 and the lower intermediate air passage 5132. The air inlet passage 511 and the air outlet passage 512 are staggered vertically, with the air inlet passage 511 connected to the lower intermediate air passage 5132 and the air outlet passage 512 connected to the upper intermediate air passage 5131. Figure 9 As shown, the bottom end of the lower valve stem 4 is configured as a conical surface 412. (As indicated...) Figure 2 As shown, during normal testing, the conical surface 412 at the bottom of the lower valve stem 4 only extends into the upper intermediate air passage 5131, and does not contact the step portion 5133 between the upper intermediate air passage 5131 and the lower intermediate air passage 5132, ensuring that the gas can flow sequentially from the inlet passage 511 through the intermediate air passage 513 into the outlet passage 512. In emergency situations such as complete failure of the spring energy storage seal ring 10, the lower valve stem 4 can be controlled to move downwards, such as... Figure 10 As shown, the conical surface 412 at the bottom of the lower valve stem 4 comes into contact with the stepped portion 5133 of the stepped countersunk hole, thereby quickly isolating and blocking the gas flow between the air inlet 511 and the air outlet 512, further improving the safety of the test conducted in this embodiment.

[0024] The testing steps in this embodiment are as follows: Figure 3 As shown, first, the spring energy storage sealing ring 10 is fitted onto the lower valve stem 4, then the valve core 8 is fitted onto the lower valve stem 4, and then... Figure 7 As shown, the lower valve stem 4 and the upper valve stem 312 are connected by a T-shaped snap-fit ​​structure. The pressure block 7 is then connected to the upper valve stem 312 by a thread. The pressure block 7 is then connected to the tooling base 1 by a thread. The pressure block 7 is then locked onto the tooling base 1 using a locking nut 13. The upper valve stem 312 is then connected to the rotating shaft 311 via a coupling 313. Finally, the cover 2 is placed on the tooling base 1 and locked onto the tooling base 1 with bolts 12. At this time, the rotating shaft 311 passes through the top of the cover 2 and is connected to the power mechanism. After the connection is completed, the power mechanism drives the rotating shaft 311 and the upper valve stem 312 to rotate. Due to the threaded structure between the upper valve stem 312 and the pressure block 7, the upper valve stem 312 will move up and down along the pressure block 7. Due to the T-shaped snap-fit ​​structure between the upper valve stem 312 and the lower valve stem 4, the lower valve stem 4 will also move up and down reciprocally, thus simulating the reciprocating use scenario. At this point, gas is introduced into the test airway 5, and then the leak test port 11 of the cover 2 is checked to see if any gas is leaking out from the leak test port 11, thereby conducting a gas leakage test on the spring energy storage sealing ring.

[0025] Example 2: The difference from Example 1 is as follows: Figure 11As shown, the fixture also includes a cryogenic chamber 15 filled with liquid nitrogen 16. The fixture base 1 is placed inside the cryogenic chamber 15, and the liquid nitrogen 16 surrounds the outside of the fixture base 1. Thus, by standardizing the design of the test fixture, it can achieve reciprocating motion even at ultra-low temperatures, meeting the requirements for reciprocating ultra-low temperature testing of the spring energy storage sealing ring. Furthermore, the testing personnel do not need to operate it manually; they only need to perform leak detection on the test piece from the operating table, greatly improving the safety of the experiment. Here, when performing ultra-low temperature testing, since the fixture base 1 is immersed in liquid nitrogen 16, the sealing ring 17 needs to be replaced with a metal spiral wound gasket.

[0026] In summary, this utility model, through the aforementioned structural design, utilizes the reciprocating motion of the lower valve stem in the up-and-down direction to simulate the actual usage scenario of the spring energy storage seal ring, conducting gas leakage tests on the spring energy storage seal ring. This ensures the sealing performance of the spring energy storage seal ring product and improves the safety of the equipment in daily operating conditions. The introduction of a pneumatic actuator and time relay into the power mechanism completely frees up manual labor during testing, avoiding unknown risks caused by seal failure of the test piece. Simultaneously, a counter is added, making the number of reciprocating movements clearly visible, eliminating the need for manual counting and making the data more reliable. The separate design of the rotating shaft of the testing fixture significantly reduces maintenance costs. When the shaft wears, only the damaged part needs to be replaced, while reducing friction greatly increases service life. The addition of a locking nut at the connection significantly improves the reliability of the connection, preventing loosening due to vibration and impact during testing, and ensuring the stability and safety of the fixture. By standardizing the design of the test fixture, it can achieve reciprocating motion even at ultra-low temperatures, thus meeting the requirements for reciprocating ultra-low temperature testing of spring energy storage seals. Moreover, the test personnel do not need to operate it manually at all; they only need to perform leak detection on the test piece from the operating table, which greatly improves the safety of the experiment.

[0027] In the embodiments, "multiple" refers to "two or more". The above embodiments are for illustrative purposes only and are not intended to limit the present invention. Those skilled in the art can make various changes or modifications without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions should also fall within the protection scope of the present invention, which should be defined by the claims.

Claims

1. A tooling for reciprocating leakage testing of spring energy storage sealing rings, characterized in that: The device includes a fixture base, a cover, a transmission rod, and a lower valve stem. A test air passage is formed inside the fixture base, and a blind hole is formed at the top of the fixture base. The cover is tightly fitted onto the top of the fixture base, and its inner cavity communicates with the test air passage through the blind hole. A pressure block and a valve core are installed inside the blind hole. The pressure block presses the valve core firmly against the bottom of the blind hole. The lower valve stem is located inside the pressure block, and its bottom end passes through the valve core and extends into the test air passage. A sealing groove is formed between the lower valve stem, the valve core, and the blind hole, allowing the tested spring energy storage sealing ring to... The spring-loaded sealing ring is fitted onto the bottom end of the lower valve stem and located within the sealing groove, blocking the passage between the test air channel and the inner cavity of the cover. One end of the transmission rod passes through the top of the cover and extends into the pressure block, engaging with the top of the lower valve stem for transmission. The movement of the transmission rod drives the lower valve stem to reciprocate in the up-down direction. A leak test port is also provided on the cover. During testing, the leak test port is used to check whether gas can flow from the test air channel along the blind hole into the inner cavity of the cover, thereby testing the sealing performance of the spring-loaded sealing ring.

2. The tooling according to claim 1, characterized in that: The blind hole includes an upper hole at the top of the tooling base and a lower hole at the bottom of the upper hole. The inner diameter of the lower hole is smaller than the inner diameter of the upper hole, thus forming a stepped countersunk hole between the upper and lower holes. An internal thread is formed on the inner circumferential surface of the upper hole. The pressure block is a hollow column with an external thread on its outer circumferential surface. The valve core includes a hollow column and a flange on the outer circumferential surface of one end of the column. One end of the valve core column is inserted into the lower hole, and one end face of the valve core flange contacts the bottom of the upper hole. The external thread of the pressure block is then threaded into the internal thread of the upper hole of the blind hole, and the pressure block is tightened into the blind hole. After tightening, the pressure block presses the valve core into the bottom of the blind hole, leaving a gap H1 between the end face of the valve core column and the bottom of the lower hole. The test air passage includes a horizontally arranged inlet air passage, an outlet air passage, and an intermediate air passage disposed between the inlet air passage and the outlet air passage. The inlet air passage is connected to the outlet air passage through the intermediate air passage, and the intermediate air passage is also connected to the bottom end of the lower hole. When the bottom end of the lower valve stem passes through the inner cavity of the valve core column and extends into the intermediate air passage, a sealing groove is formed between the lower valve stem, one end face of the valve core column, and the lower hole of the blind hole.

3. The tooling according to claim 2, characterized in that: A locking nut is threaded onto the outer circumferential surface of the pressure block.

4. The tooling according to claim 2, characterized in that: The transmission rod includes a rotating shaft and an upper valve rod. One end of the rotating shaft passes through the top of the cover and extends into the inner cavity of the cover, where it is connected to the top of the upper valve rod via a coupling. An external thread is provided on the outer circumferential surface of the upper valve rod, and an internal thread is provided on the inner circumferential surface of the pressure block. The external thread of the rod and the internal thread of the pressure block are threaded together, thereby screwing one end of the upper valve rod into the inner cavity of the pressure block. A T-shaped slot is provided at one end of the upper valve rod, and a T-shaped protrusion is provided at the top of the lower valve rod. The T-shaped protrusion engages with the T-shaped slot, thereby connecting the top ends of the upper and lower valve rods.

5. The tooling according to claim 4, characterized in that: The other end of the shaft is connected to a power mechanism, which can drive the shaft to rotate.

6. The tooling according to claim 5, characterized in that: The power mechanism is a pneumatic actuator with time relay control.

7. The tooling according to claim 4, characterized in that: A sealing ring one is provided at one end of the rotating shaft where it passes through the top of the cover, and a sealing ring two can also be provided on the contact surface between the cover and the top of the tooling base.

8. The tooling according to claim 4, characterized in that: The intermediate air passage includes an upper intermediate air passage and a lower intermediate air passage connected to the upper intermediate air passage. The inner diameter of the lower intermediate air passage is less than the inner diameter of the upper intermediate air passage, thereby forming a stepped countersunk hole between the upper and lower intermediate air passages. The air inlet passage is connected to the lower intermediate air passage, and the air outlet passage is connected to the upper intermediate air passage. The bottom end of the lower valve stem is set as a conical surface. By moving the lower valve stem downward, the conical surface at the bottom end of the lower valve stem contacts the stepped part of the stepped countersunk hole, which can isolate and block the gas flow between the air inlet passage and the air outlet passage.

9. The tooling according to any one of claims 1 to 8, characterized in that: The fixture also includes a cryogenic chamber filled with liquid nitrogen, and the fixture base is placed inside the cryogenic chamber with the liquid nitrogen encasing the outside of the fixture base.

Images