Fatigue detection device and method for low-temperature medium rupture disk

Abstract

The invention discloses a low-temperature medium rupture disk fatigue detection device and method, and relates to the technical field of rupture disk fatigue detection.The low-temperature medium rupture disk fatigue detection device comprises a test container, a backpressure container, a detection device, an adjusting device and a control device; wherein the test container is used for accommodating a low-temperature medium, the test container is communicated with a first opening, and a first heat insulation structure is arranged on the outer side of the test container; the internal pressure of the backpressure container is adjustable, the backpressure container is provided with a second opening, the second opening corresponds to the first opening, and the second opening and the first opening abut against the two opposite sides of the rupture disk to be detected in a sealed mode respectively; the adjusting device is used for adjusting the internal pressure of the backpressure container; the control device is electrically connected with the adjusting device and used for controlling the adjusting device to work according to the detection result of the detection device. According to the technical scheme provided by the invention, the fatigue test of the low-temperature medium rupture disk can be quickly carried out, the test efficiency is improved, and the temperature in the test process is relatively stable.

Description

Technical Field

[0001] This invention relates to the field of rupture disc fatigue testing technology, and particularly to a device and method for testing fatigue of rupture discs in cryogenic media. Background Technology

[0002] Rupture discs are one of the important safety accessories for pressure-bearing special equipment. To ensure that the safety performance of rupture discs meets the technical requirements, fatigue testing must be conducted on them.

[0003] Compared to conventional rupture discs, cryogenic rupture discs operate in cryogenic environments. Since rupture discs and safety valves are both safety relief devices, and there are no specific requirements for cryogenic rupture discs in relevant national standards and safety technical specifications, testing can be conducted with reference to cryogenic safety valves. When conducting fatigue testing on cryogenic safety valves, the attached [document / reference] can be used as a reference. Figure 1 The arrangement of the test apparatus is specified in Annex H of TSG ZF001-2006.

[0004] Its working principle is to install the safety valve or rupture disc on the connection plate of the test container, pass liquid or other media with low temperature evaporation characteristics in the container, close the low temperature shut-off valve of the liquid storage container, and then close the shut-off valve on the connection plate of the test container, so that the low temperature medium in the container will naturally vaporize and the pressure will rise, and observe the test process and situation of the safety valve or rupture disc.

[0005] It should be noted that the pressure increase in the test container is achieved through natural vaporization. Natural vaporization is achieved through heat exchange. Due to the presence of the insulation layer, heat exchange is limited, resulting in a slow pressure increase during natural vaporization and affecting test efficiency. Furthermore, during the prolonged vaporization process of the liquefied gas, the temperature may fluctuate significantly due to heat exchange during vaporization, making it difficult to ensure relative temperature stability during the test.

[0006] Therefore, there is an urgent need for a fatigue testing device and method for cryogenic rupture discs to improve the testing efficiency of cryogenic rupture discs and ensure relatively stable temperature during the testing process. Summary of the Invention

[0007] The main objective of this invention is to propose a fatigue testing device and method for cryogenic rupture discs, which aims to improve the testing efficiency of cryogenic rupture discs in a cryogenic environment and ensure relatively stable temperature during the testing process.

[0008] To achieve the above objectives, the present invention provides a low-temperature dielectric rupture disc fatigue testing device, comprising: A test container for containing a low-temperature medium, the test container having a first opening, and a first heat insulation structure provided on the outside of the test container; A back pressure container, the internal pressure of which is adjustable, the back pressure container having a second opening corresponding to the first opening, the second opening and the first opening respectively sealing and abutting against the opposite sides of the rupture disc to be tested; The detection device is used to detect the surface temperature T1 of the rupture disc to be tested, the temperature T2 at the first opening, the pressure P1 on the side of the rupture disc to be tested facing the first opening, the temperature T3 at the second opening, and the pressure P2 on the side of the rupture disc to be tested facing the second opening. Adjustment device for adjusting the internal pressure of the back pressure vessel; and, A control device, electrically connected to the regulating device, is used to control the operation of the regulating device based on the detection result of the detection device.

[0009] In one embodiment, the cryogenic medium rupture disc fatigue testing device further includes: A liquid nitrogen storage tank, which contains liquid nitrogen as a cryogenic medium, and the outer side of the liquid nitrogen storage tank is provided with a second heat insulation structure; and, A connecting channel connects the liquid nitrogen storage tank and the test container, and a connecting valve is provided on the connecting channel; The control device is also used to control the connecting valve.

[0010] In one embodiment, the liquid nitrogen storage tank stores nitrogen gas and liquid nitrogen; The connecting channel includes a main channel and an air inlet branch channel and a liquid inlet branch channel connected to and arranged in parallel with the main channel. The air inlet branch channel is connected to the upper end of the liquid nitrogen storage tank, and the liquid inlet branch channel is connected to the lower end of the liquid nitrogen storage tank. The air intake branch channel is equipped with an air intake valve, the liquid intake branch channel is equipped with a liquid intake valve, the connecting valve is located on the main channel, and the control device is also used to control the air intake valve and the liquid intake valve.

[0011] In one embodiment, a booster is provided on the main flow channel; The control device is also used to control the booster.

[0012] In one embodiment, the connecting channel further includes a first branch channel, a second branch channel, and a liquid-distributing branch channel. The first branch channel and the second branch channel are arranged in parallel and one end of each is connected to the main channel. The other end of the first branch channel is connected to the upper end of the test container, and the other end of the second branch channel is connected to the lower end of the test container. The liquid-distributing branch channel is arranged in parallel with the booster. The first branch channel is provided with a first valve, the second branch channel is provided with a second valve, the liquid-distributing branch channel is provided with a liquid-distributing valve, and the control device is also used to control the first valve, the second valve and the liquid-distributing valve.

[0013] In one embodiment, a safety valve is further provided on the main flow channel, the safety valve being located between the booster and the test vessel; and / or, The regulating device includes an air source, a third valve, and a fourth valve. The air source is connected to the back pressure container and includes compressed air. The third valve controls the entry of the compressed air into the back pressure container, and the fourth valve controls the discharge of the compressed air; and / or, The lower end of the test container is equipped with a drain valve; and / or, The first thermal insulation structure includes a vacuum insulation layer; and / or, The second thermal insulation structure includes a vacuum insulation layer.

[0014] This invention also proposes a method for fatigue testing of cryogenic rupture discs, used in the cryogenic rupture disc fatigue testing device as described in any of the above claims. The cryogenic rupture disc fatigue testing device includes a liquid nitrogen storage tank, a connecting channel, and a connecting valve. The regulating device includes a gas source, a third valve, and a fourth valve. The cryogenic rupture disc fatigue testing method includes the following steps: S01: After the rupture disc to be tested is sealed between the first opening and the second opening, the connecting valve is opened to inject liquid nitrogen into the test container; S02: Obtain the pressure P1 on the side wall of the rupture disc to be tested facing the first opening and the temperature T2 at the first opening. After P1 and T2 meet the preset conditions, control the connecting valve to close. S03: When the fourth valve is closed and the third valve is open, control the air source to operate to introduce compressed air into the back pressure container until P2 reaches the preset value, and then control the third valve to close. S04: Control the fourth valve to open so that compressed air can be discharged; S05: After repeating steps S03 and S04 a specified number of times, control the fourth valve to close.

[0015] In one embodiment, the connecting channel further includes an inlet branch channel and an inlet valve, a first branch channel and a first valve, a second branch channel and a second valve, and a distributing branch channel and a distributing valve. Step S02 includes the following steps: S021: After controlling the opening of the liquid inlet valve, the connecting valve, and the liquid distribution valve, control the first valve and the second valve to open alternately.

[0016] In one embodiment, the connecting channel further includes an intake branch channel and an intake valve, and a booster is provided on the main channel. After step S021, the following steps are also included: S022: After closing the liquid inlet valve, the liquid distribution valve, the first valve and the second valve, control the air inlet valve, the booster and the first valve to open until P1 reaches the specified pressure; S023: Control the opening of the inlet valve, the distributor valve and the first valve until T2 reaches the specified temperature.

[0017] In one embodiment, the third valve has a delayed response interval, and the steps of the cryogenic medium rupture disc fatigue detection method further include: A01: According to the law of conservation of mass, the amount of dry air in the back pressure container is n = P2 * V / R * T3; where V is the volume of the back pressure container and R is the universal gas constant. A02: Obtain the maximum mass of dry air that the back pressure container can hold, M. 大 =M 平 *P2*V / R*T3; where M 平 The average molar mass of the air introduced into the back pressure container; A03: Obtain the back pressure container's capacity to exceed the maximum dry air mass M 大 Fluctuating air mass ΔM=x*M 平 *P2*V / R*T3; where x is the sensitivity requirement value of the rupture disc to be tested; A04: Obtain the relationship between the back pressure vessel volume V and other technical parameters: V=A*v*t*R*T3 / x*M 平 *P2; where A is the flow area of ​​the third valve, v is the gas flow rate, and t is the corresponding delay time of the third valve.

[0018] In the technical solution of this invention, the rupture disc to be tested is placed between a first opening and a second opening. The temperature T2 of the rupture disc near the first opening is maintained by the low-temperature medium contained in the test container. By adjusting the pressure inside the back pressure container, the pressure difference between the two sides of the rupture disc to be tested is changed, thereby simulating the pressure received by the rupture disc in the actual working environment. The pressure calculation formula is the pressure P on the rupture disc to be tested P=P1-P2. In this way, the low-temperature medium rupture disc fatigue test can be carried out quickly by adjusting the internal pressure of the back pressure container, improving the test efficiency and ensuring the relative temperature stability during the test. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of a low-temperature medium burst disc fatigue testing device in the prior art. Figure 2 A schematic diagram of the low-temperature medium rupture disc fatigue testing device provided in this application; Figure 3 This is a schematic diagram of the equipment structure of the hardware operating environment involved in the low-temperature medium rupture disc fatigue detection method in this application embodiment; Figure 4 This is a schematic flowchart of an embodiment of the low-temperature medium rupture disc fatigue testing method provided in this application.

[0021] Explanation of reference numerals in the attached diagram: 100, Low-temperature medium rupture disc fatigue testing device; 1, Test container; 11, First heat insulation structure; 2, Back pressure container; 3, Rupture disc to be tested; 4, Adjustment device; 41, Third valve; 42, Fourth valve; 5, Liquid nitrogen storage tank; 51, Second heat insulation structure; 6a, Connecting valve; 6b, Air inlet valve; 6c, Liquid inlet valve; 6d, First valve; 6e, Second valve; 6f, Distributing valve; 6g, Safety valve; 7, Pressure booster.

[0022] 1' Test container; 2' Connecting plate; 3' Low temperature shut-off valve; 4' Insulation layer.

[0023] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0025] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0026] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0027] In the existing technology, please refer to Figure 1 A connecting plate 2' is connected to the test container 1', which is used to install the rupture disc to be tested. The test container 1' is also connected to a cryogenic medium storage container. Because a low-temperature environment needs to be maintained, it is necessary to prevent the cryogenic medium from absorbing too much external heat and prematurely vaporizing. Therefore, an insulation layer 4' is also provided on the outside of the test container 1' and the cryogenic medium storage container. Its working principle is that after the cryogenic medium is introduced into the test container 1', the cryogenic shut-off valve 3' is closed, allowing the cryogenic medium in the test container 1' to absorb external heat and naturally vaporize, thereby increasing the pressure inside the test container 1' and observing the test process and conditions of the rupture disc. During this process, the presence of the insulation layer 4' results in slow heat exchange, low test efficiency, and as time goes on, the temperature fluctuation of the test environment of the rupture disc is large during the process of the cryogenic medium absorbing external heat, making it difficult to ensure a relatively stable temperature during the experiment.

[0028] This invention proposes a low-temperature medium rupture disc fatigue testing device 100 to improve the testing efficiency of low-temperature medium rupture discs and ensure relatively stable temperature during the testing process.

[0029] Please see Figure 2In one embodiment of the present invention, the cryogenic medium rupture disc fatigue testing device 100 includes a test container 1, a back pressure container 2, a testing device, an adjusting device 4, and a control device. The test container 1 is used to contain a cryogenic medium and has a first opening. A first heat insulation structure 11 is provided on the outer side of the test container 1. The internal pressure of the back pressure container 2 is adjustable. The back pressure container 2 has a second opening corresponding to the first opening, and the second opening and the first opening are respectively sealed against opposite sides of the rupture disc 3 to be tested. The testing device is used to detect the surface temperature T1 of the rupture disc 3 to be tested, the temperature T2 at the first opening, the pressure P1 on the side of the rupture disc 3 facing the first opening, the temperature T3 at the second opening, and the pressure P2 on the side of the rupture disc 3 facing the second opening. The adjusting device 4 is used to adjust the internal pressure of the back pressure container 2. The control device is electrically connected to the adjusting device 4 and is used to control the operation of the adjusting device 4 according to the detection results of the testing device.

[0030] In the technical solution of this invention, the rupture disc 3 to be tested is placed between the first opening and the second opening. The temperature T2 of the rupture disc 3 near the first opening is maintained by the low-temperature medium contained in the test container 1. By adjusting the pressure inside the back pressure container 2, the pressure difference between the two sides of the rupture disc 3 to be tested is changed, thereby simulating the pressure received by the rupture disc in the actual working environment. The pressure calculation formula is the pressure P received by the rupture disc 3 to be tested P=P1-P2. In this way, the low-temperature medium rupture disc fatigue test can be carried out quickly by adjusting the internal pressure of the back pressure container 2, improving the test efficiency and ensuring the relative temperature stability during the test.

[0031] It should be noted that the present invention does not limit the specific form of the cryogenic medium; for example, cryogenic liquids or other media with cryogenic evaporation characteristics are acceptable. In an embodiment of the present invention, the cryogenic medium rupture disc fatigue testing device 100 further includes a liquid nitrogen storage tank 5 and a connecting channel; the liquid nitrogen storage tank 5 contains liquid nitrogen as a cryogenic medium, and a second heat insulation structure 51 is provided on the outside of the liquid nitrogen storage tank 5; the connecting channel connects the liquid nitrogen storage tank 5 and the test container 1, and a connecting valve 6a is provided on the connecting channel; wherein, the control device is also used to control the connecting valve 6a. That is to say, the present invention uses liquid nitrogen as the cryogenic medium and controls the input of liquid nitrogen into the test container 1 through the connecting valve 6a to control the test environment of the rupture disc 3 to be tested.

[0032] In an embodiment of the present invention, the liquid nitrogen storage tank 5 stores nitrogen gas and liquid nitrogen; the connecting channel includes a main channel and an inlet branch channel and a liquid inlet branch channel connected to and arranged in parallel with the main channel. The inlet branch channel connects to the upper end of the liquid nitrogen storage tank 5, and the liquid inlet branch channel connects to the lower end of the liquid nitrogen storage tank 5; wherein, an inlet valve 6b is provided on the inlet branch channel, a liquid inlet valve 6c is provided on the liquid inlet branch channel, and a connecting valve 6a is provided on the main channel; the control device is also used to control the inlet valve 6b and the liquid inlet valve 6c. That is to say, since the liquid nitrogen storage tank 5 stores both nitrogen gas and liquid nitrogen, the cryogenic medium rupture disc fatigue testing device 100 provided by the present invention can not only control the temperature inside the test container 1 by inputting liquid nitrogen, but also introduce nitrogen gas to increase the pressure inside the test container 1, so as to better simulate the real working environment.

[0033] Furthermore, in an embodiment of the present invention, a booster 7 is provided on the main flow channel; wherein, the control device is also used to control the booster 7. That is, by providing a booster 7 on the main flow channel, when the nitrogen gas is introduced into the test container 1, the booster 7 can pressurize the nitrogen gas before it is introduced into the test container 1.

[0034] During the process of introducing liquid nitrogen into the test container 1 for cooling, in order to make the cooling of the test container 1 more uniform, in this embodiment of the invention, the connecting channel further includes a first branch channel, a second branch channel, and a liquid-distributing branch channel. The first branch channel and the second branch channel are arranged in parallel and one end of each is connected to the main channel. The other end of the first branch channel is connected to the upper end of the test container 1, and the other end of the second branch channel is connected to the lower end of the test container 1. The liquid-distributing branch channel is arranged in parallel with the booster 7. A first valve 6d is provided on the first branch channel, a second valve 6e is provided on the second branch channel, and a liquid-distributing valve 6f is provided on the liquid-distributing branch channel. The control device is also used to control the first valve 6d, the second valve 6e, and the liquid-distributing valve 6f.

[0035] In other words, by providing flow channels at both the upper and lower ends of the test container 1 for liquid nitrogen circulation, the uneven cooling of the test container 1 is prevented from occurring due to localized excessively low temperatures. Furthermore, since the liquid distribution channel and the booster 7 are connected in parallel, when liquid nitrogen needs to be introduced into the test container 1, simply controlling the booster 7 to disconnect so that the liquid nitrogen does not pass through it can prevent damage to the booster 7. It should be noted that, since the two flow channels in this application are respectively located at the upper and lower ends of the test container 1, if the first valve 6d and the second valve 6e are opened simultaneously to allow liquid nitrogen to flow into the test container 1 from both ends at the same time, the flow rates of the liquid nitrogen in the first and second flow channels will inevitably differ. This situation will also lead to uneven cooling of the test container 1. Therefore, to avoid this situation, in the embodiments of this invention, when liquid nitrogen needs to be introduced into the test container 1, the first valve 6d and the second valve 6e are opened alternately. In other embodiments of the present invention, the first branch channel and the second branch channel may be located on opposite sides of the test container 1 in the horizontal direction, and the opening of the first valve 6d and the second valve 6e may be controlled simultaneously, which can also avoid the problem of different flow rates of liquid nitrogen in the two channels.

[0036] In an embodiment of the present invention, a safety valve 6g is also provided on the main flow channel, and the safety valve 6g is located between the booster 7 and the test container 1. By providing a safety valve 6g downstream of the booster 7, safety problems caused by overpressure can be prevented when pressurized nitrogen is introduced into the test container 1. In another embodiment of the present invention, the regulating device 4 includes a gas source, a third valve 41, and a fourth valve 42. The gas source is connected to the back pressure container 2, and the gas source includes compressed air. The third valve 41 is used to control the entry of the compressed air into the back pressure container 2, and the fourth valve 42 is used to control the discharge of the compressed air. That is, in this embodiment, compressed air is introduced into the back pressure container 2 through the third valve 41, and the compressed air is discharged through the fourth valve 42, thereby achieving rapid adjustment of the pressure in the back pressure container 2 (i.e., rapid adjustment of P2), and thus rapid adjustment of the pressure P on the rupture disc 3 to be tested.

[0037] In another embodiment of the present invention, a drain valve (not shown) is provided at the lower end of the test container 1. The liquid nitrogen in the test container 1 is drained by the drain valve. It should be noted that the present invention does not limit whether the drain valve can simultaneously drain the nitrogen gas in the test container 1. For example, the nitrogen gas can be drained together by the drain valve, or an additional exhaust valve can be provided to drain the nitrogen gas. Furthermore, the present invention does not limit the amount of nitrogen gas and liquid nitrogen discharged; for example, it can be reintroduced into the liquid nitrogen storage tank 5 after cooling and depressurization for reuse, or it can be processed in other ways. In yet another embodiment of the present invention, the first heat insulation structure 11 includes a vacuum heat insulation layer. By providing a vacuum heat insulation layer on the outside of the test container 1, the temperature of the test container 1 is kept stable during the test, maintaining a stable test environment. In yet another embodiment of the present invention, the second heat insulation structure 51 includes a vacuum heat insulation layer. By providing a vacuum heat insulation layer on the outside of the liquid nitrogen storage tank 5, the temperature of the liquid nitrogen in the liquid nitrogen storage tank 5 is kept stable.

[0038] It should be noted that the above-mentioned embodiments with safety valve 6g, the regulating device 4 including a gas source, a third valve 41 and a fourth valve 42, the embodiment with the drain valve, the first heat insulation structure 11 including a vacuum heat insulation layer, and the second heat insulation structure 51 including a vacuum heat insulation layer can be used individually or simultaneously, and the present invention does not limit this.

[0039] In addition, the control device provided in this application includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform the cryogenic dielectric rupture disc fatigue detection method in the following embodiments.

[0040] The following is for reference. Figure 4 The diagram illustrates a structural schematic of a control device suitable for implementing embodiments of this application. The control device in the embodiments of this application may include, but is not limited to, mobile terminals such as mobile phones, laptops, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), in-vehicle terminals (e.g., in-vehicle navigation terminals), and fixed terminals such as digital TVs and desktop computers. Figure 4 The control device shown is merely an example and should not impose any limitation on the functionality and scope of use of the embodiments of this application.

[0041] like Figure 4 As shown, the control device may include a processing device 1001 (e.g., a central processing unit, a graphics processing unit, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 1002 or a program loaded from a storage device 1003 into a random access memory (RAM) 1004. The RAM 1004 also stores various programs and data required for the operation of the control device. The processing device 1001, ROM 1002, and RAM 1004 are interconnected via a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Typically, the following systems can be connected to the I / O interface 1006: input devices 1007 including, for example, a touchscreen, touchpad, keyboard, mouse, image sensor, microphone, accelerometer, gyroscope, etc.; output devices 1008 including, for example, a liquid crystal display (LCD), speaker, vibrator, etc.; storage devices 1003 including, for example, magnetic tape, hard disk, etc.; and communication devices 1009. Communication device 1009 allows the control device to communicate wirelessly or wiredly with other devices to exchange data. Although the figure shows a control device with various systems, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems may be implemented alternatively.

[0042] Specifically, according to the embodiments disclosed in this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments disclosed in this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication device, or installed from storage device 1003, or installed from ROM 1002. When the computer program is executed by processing device 1001, it performs the functions defined in the methods of the embodiments disclosed in this application.

[0043] It should be understood that the various parts disclosed in this application can be implemented using hardware, software, firmware, or a combination thereof. In the description of the above embodiments, specific features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples.

[0044] Please refer to Figure 3The present invention also proposes a method for fatigue testing of cryogenic rupture discs, used in the cryogenic rupture disc fatigue testing device 100 mentioned in any of the above embodiments. The cryogenic rupture disc fatigue testing device 100 includes a liquid nitrogen storage tank 5, a connecting channel, and a connecting valve 6a. The regulating device 4 includes a gas source, a third valve 41, and a fourth valve 42. The cryogenic rupture disc fatigue testing method includes the following steps: S01: After the rupture disc 3 to be tested is sealed between the first opening and the second opening, the connecting valve 6a is opened to inject liquid nitrogen into the test container 1; In this step, if the seal between the rupture disc 3 to be tested and the first opening is insufficient, the temperature inside the test container 1 may drop too quickly, and P1 may not meet the test requirements. If the seal between the rupture disc 3 to be tested and the second opening is insufficient, P2 may not meet the test requirements, and the test may not be able to be carried out.

[0045] S02: Obtain the pressure P1 on the side wall of the rupture disc 3 facing the first opening and the temperature T2 at the first opening. After P1 and T2 meet the preset conditions, control the connecting valve 6a to close. This step is to test the test environment of the rupture disc 3 to be tested. If either P1 or T2 fails to meet the test requirements, the test environment needs to be adjusted. It should be noted that the present invention does not limit the specific values ​​of the preset conditions, but can be adjusted according to the actual application environment of the rupture disc 3 to be tested.

[0046] S03: When the fourth valve 42 is closed and the third valve 41 is open, control the air source to work to introduce compressed air into the back pressure container 2 until P2 reaches the preset value, and then control the third valve 41 to close. After confirming that the test environment of the rupture disc 3 meets the preset conditions, P2 can be adjusted by introducing compressed air into the back pressure container 2. Since the pressure P on the rupture disc 3 is P = P1 - P2, the pressure received by the rupture disc 3 can be adjusted, thereby enabling the rupture disc 3 to complete the fatigue test under a specific test environment. It should be noted that the present invention does not limit the specific method of adjusting P2. Since the side of the rupture disc near the second opening is usually air under normal conditions, using compressed air as the pressurizing medium is closer to the actual working conditions. Moreover, introducing compressed air allows for faster and more convenient adjustment of P2. Therefore, compressed air is used to adjust P2 in the embodiments of the present invention. In other embodiments of the present invention, other inert gases or substances that are easy to evaporate and pressurize under the test conditions can also be introduced. The present invention does not impose specific limitations. As for the preset value of P2, the present invention does not limit it and can adjust it according to the actual situation.

[0047] S04: Control the fourth valve 42 to open so that compressed air can be discharged; S05: After repeating steps S03 and S04 a specified number of times, control the fourth valve 42 to close.

[0048] It should be noted that steps S03 and S04 constitute one cycle of fatigue load. Multiple cycles of this fatigue load are required to complete the low-temperature medium bursting disc fatigue test. The specified number of cycles can be adjusted according to the actual situation, and this invention does not impose any restrictions.

[0049] Furthermore, the connecting flow channel also includes an inlet branch channel and an inlet valve 6c, a first branch channel and a first valve 6d, a second branch channel and a second valve 6e, and a distributing branch channel and a distributing valve 6f. Step S02 includes the following steps: S021: After controlling the opening of the liquid inlet valve 6c, the connecting valve 6a, and the liquid distribution valve 6f, control the first valve 6d and the second valve 6e to open alternately.

[0050] It should be noted that this step involves introducing liquid nitrogen into the empty test container 1. Since the temperature of the empty test container 1 is ambient temperature, which is higher than the temperature of the liquid nitrogen, in order to prevent losses caused by uneven cooling of the test container 1, it is necessary to ensure that all parts of the test container 1 cool down as evenly as possible during the liquid nitrogen introduction process. Specifically, the inlet valve 6c, the connecting valve 6a, and the distributing valve 6f are controlled to open, introducing the liquid nitrogen into the main channel. Then, the first valve 6d and the second valve 6e are controlled to open alternately, so that the liquid nitrogen enters the test container 1 alternately from the upper and lower ends, achieving uniform cooling of the test container 1.

[0051] In an embodiment of the present invention, the connecting channel further includes an intake branch channel and an intake valve 6b, and a booster 7 is provided on the main channel. After step S021, the following steps are further included: S022: After closing the liquid inlet valve 6c, the liquid distribution valve 6f, the first valve 6d and the second valve 6e, control the air inlet valve 6b, the booster 7 and the first valve 6d to open until P1 reaches the specified pressure; After step S021, if it is detected that P1 has not reached the preset condition, nitrogen gas is introduced to increase P1 until the preset condition is reached.

[0052] S023: Control the opening of the inlet valve 6c, the dispensing valve 6f, and the first valve 6d until T2 reaches the specified temperature.

[0053] After step S022, if it is detected that T2 has not reached the specified temperature, the first valve 6d is opened to spray liquid nitrogen from above the test container 1, thereby cooling the test container 1 and further reducing T2 until the specified temperature is reached.

[0054] In an embodiment of the present invention, the third valve 41 has a delayed response interval, and the steps of the cryogenic medium rupture disc fatigue detection method further include: A01: According to the law of conservation of mass, the amount of dry air in the back pressure container 2 is n = P2 * V / R * T3; where V is the volume of the back pressure container 2 and R is the universal gas constant. In this step, P is in Pascals (Pa), V is in cubic meters (m3), n is in mol, T is in Kelvin (K), and R is 8.314 J / (mol·K).

[0055] A02: Obtain the maximum mass M of dry air that the back pressure container 2 can hold. 大 =M 平 *P2*V / R*T3; where M 平 The average molar mass of the air introduced into the back pressure container 2; In this step, take M. 平 It is 29 g / mol = 0.029 kg / mol.

[0056] A03: The back pressure container 2 can exceed the maximum mass M of dry air. 大 Fluctuating air mass ΔM=x*M 平 *P2*V / R*T3; where x is the sensitivity requirement value of the rupture disc 3 to be tested; It should be noted that in this step, the sensitivity requirement value x of the rupture disc refers to the pressure within which the rupture disc can burst. For example, in the embodiment of this invention, x is ±5%, meaning that the rupture disc can burst within ±5% of the required pressure. Based on this, since negative deviation has no effect on the use and testing of the rupture disc, x = 5% is taken. (The remaining text appears to be a separate, unrelated statement about x = 5%, R = 8.314 J / (mol·K), and M...) 平 =29 g / mol=0.029Kg / mol Substituting this into ΔM=x*M 平 *P2*V / R*T3, we get ΔM=0.029*0.05P2*V / 8.314*T3, where T3 is the temperature of the rupture disc near the back pressure container 2, which is also the temperature of the dry air. Calculated at room temperature, T3=27℃=300K, we get ΔM=5.8134*10 -7 P2*V.

[0057] A04: Obtain the relationship between the volume V of the back pressure vessel 2 and other technical parameters: V=A*v*t*R*T3 / x*M 平 *P2; where A is the flow area of ​​the third valve 41, v is the gas flow rate, and t is the corresponding delay time of the third valve 41.

[0058] In this step, the value of ΔM is also related to the gas flow velocity v into the back pressure container 2, the flow channel area A of the third valve 41, and the delay t of the third invention. The specific expression is ΔM = A * v * t. From step A03, we know that ΔM = 5.8134 * 10 -7 Substituting P2*V into ΔM=A*v*t, we get V=A*v*t / 5.8134*10 -7 P2, thus determining the relationship between the volume V of the back pressure vessel 2 and other technical parameters. Taking a fatigue test pressure of 2 MPa as an example, assuming the diameter of the regulating valve flow channel is 32 mm and the flow channel area A = 8 * 10 -4 m 2 The flow rate and response delay of the third valve 41 are fixed. Assuming v = 40 m / s and t = 1.5 s, substituting the parameters, we know that V = 0.413 m. 3 In other words, to ensure that the maximum pressure fluctuation does not exceed +5%, the volume of back pressure vessel 2 is not less than 0.413m³. 3 .

[0059] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention specification and drawings under the technical concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A fatigue testing device for cryogenic rupture discs, characterized in that, include: A test container for containing a low-temperature medium, the test container having a first opening, and a first heat insulation structure provided on the outside of the test container; A back pressure container, wherein the internal pressure of the back pressure container is adjustable, the back pressure container is provided with a second opening, the second opening is corresponding to the first opening, and the second opening and the first opening are respectively sealed and abutted against the opposite sides of the rupture disc to be tested; The detection device is used to detect the surface temperature T1 of the rupture disc to be tested, the temperature T2 at the first opening, the pressure P1 on the side of the rupture disc to be tested facing the first opening, the temperature T3 at the second opening, and the pressure P2 on the side of the rupture disc to be tested facing the second opening. A regulating device for regulating the internal pressure of the back pressure container; as well as, A control device, electrically connected to the regulating device, is used to control the operation of the regulating device based on the detection result of the detection device.

2. The low-temperature medium rupture disc fatigue testing device as described in claim 1, characterized in that, The cryogenic medium rupture disc fatigue testing device also includes: A liquid nitrogen storage tank, which contains liquid nitrogen as a cryogenic medium, and the outer side of the liquid nitrogen storage tank is provided with a second heat insulation structure; and, A connecting channel connects the liquid nitrogen storage tank and the test container, and a connecting valve is provided on the connecting channel; The control device is also used to control the connecting valve.

3. The low-temperature medium rupture disc fatigue testing device as described in claim 2, characterized in that, The liquid nitrogen storage tank contains nitrogen gas and liquid nitrogen; The connecting channel includes a main channel and an air inlet branch channel and a liquid inlet branch channel connected to and arranged in parallel with the main channel. The air inlet branch channel is connected to the upper end of the liquid nitrogen storage tank, and the liquid inlet branch channel is connected to the lower end of the liquid nitrogen storage tank. The air intake branch channel is equipped with an air intake valve, the liquid intake branch channel is equipped with a liquid intake valve, the connecting valve is located on the main channel, and the control device is also used to control the air intake valve and the liquid intake valve.

4. The low-temperature medium rupture disc fatigue testing device as described in claim 3, characterized in that, A turbocharger is installed on the main channel; The control device is also used to control the booster.

5. The low-temperature medium rupture disc fatigue testing device as described in claim 4, characterized in that, The connecting channel further includes a first branch channel, a second branch channel, and a liquid-distributing branch channel. The first branch channel and the second branch channel are arranged in parallel and one end of each is connected to the main channel. The other end of the first branch channel is connected to the upper end of the test container, and the other end of the second branch channel is connected to the lower end of the test container. The liquid-distributing branch channel is arranged in parallel with the booster. The first branch channel is provided with a first valve, the second branch channel is provided with a second valve, the liquid-distributing branch channel is provided with a liquid-distributing valve, and the control device is also used to control the first valve, the second valve and the liquid-distributing valve.

6. The low-temperature medium rupture disc fatigue testing device as described in claim 4, characterized in that, A safety valve is also installed on the main flow channel, the safety valve being located between the booster and the test vessel; and / or, The regulating device includes an air source, a third valve, and a fourth valve. The air source is connected to the back pressure container and includes compressed air. The third valve controls the entry of the compressed air into the back pressure container, and the fourth valve controls the discharge of the compressed air; and / or, The test container is equipped with a drain valve at its lower end; and / or, The first thermal insulation structure includes a vacuum insulation layer; and / or, The second thermal insulation structure includes a vacuum insulation layer.

7. A method for fatigue testing of cryogenic rupture discs, used in the cryogenic rupture disc fatigue testing device as described in any one of claims 1 to 6, characterized in that, The cryogenic medium rupture disc fatigue testing device includes a liquid nitrogen storage tank, a connecting channel, and connecting valves. The regulating device includes a gas source, a third valve, and a fourth valve. The cryogenic medium rupture disc fatigue testing method includes the following steps: S01: After the rupture disc to be tested is sealed between the first opening and the second opening, the connecting valve is opened to inject liquid nitrogen into the test container; S02: Obtain the pressure P1 on the side wall of the rupture disc to be tested facing the first opening and the temperature T2 at the first opening. After P1 and T2 meet the preset conditions, control the connecting valve to close. S03: When the fourth valve is closed and the third valve is open, control the air source to operate to introduce compressed air into the back pressure container until P2 reaches the preset value, and then control the third valve to close. S04: Control the fourth valve to open so that compressed air can be discharged; S05: After repeating steps S03 and S04 a specified number of times, control the fourth valve to close.

8. The fatigue testing method for cryogenic dielectric rupture discs as described in claim 7, characterized in that, The connecting flow channel further includes an inlet branch channel and an inlet valve, a first branch channel and a first valve, a second branch channel and a second valve, and a distributing branch channel and a distributing valve. Step S02 includes the following steps: S021: After controlling the opening of the liquid inlet valve, the connecting valve, and the liquid distribution valve, control the first valve and the second valve to open alternately.

9. The fatigue testing method for cryogenic dielectric rupture discs as described in claim 8, characterized in that, The connecting channel further includes an intake branch channel and an intake valve. A booster is installed on the main channel. After step S021, the following steps are also included: S022: After closing the liquid inlet valve, the liquid distribution valve, the first valve and the second valve, control the air inlet valve, the booster and the first valve to open until P1 reaches the specified pressure; S023: Control the opening of the inlet valve, the distributor valve and the first valve until T2 reaches the specified temperature.

10. The fatigue testing method for cryogenic dielectric rupture discs as described in claim 7, characterized in that, The third valve has a delayed response interval, and the steps of the cryogenic medium rupture disc fatigue detection method further include: A01: According to the law of conservation of mass, the amount of dry air in the back pressure container is n = P2 * V / R * T3; where V is the volume of the back pressure container and R is the universal gas constant. A02: Obtain the maximum mass of dry air that the back pressure container can hold, M. 大 =M 平 *P2*V / R*T3; where M 平 The average molar mass of the air introduced into the back pressure container; A03: Obtain the back pressure container's capacity to exceed the maximum dry air mass M 大 Fluctuating air mass ΔM=x*M 平 *P2*V / R*T3; where x is the sensitivity requirement value of the rupture disc to be tested; A04: Obtain the relationship between the back pressure vessel volume V and other technical parameters: V=A*v*t*R*T3 / x*M 平 *P2; where A is the flow area of ​​the third valve, v is the gas flow rate, and t is the corresponding delay time of the third valve.

Images