Pressure test method and device for gas cylinder

Abstract

The invention provides a gas cylinder pressure test method and device, and the method comprises the steps: injecting purified water into a to-be-tested gas cylinder until the ratio of the volume of the purified water in the to-be-tested gas cylinder to the total volume of the to-be-tested gas cylinder reaches a preset range; gas is injected into the to-be-detected gas cylinder until the pressure in the to-be-detected gas cylinder reaches the preset pressure, at least two pressure gauges are arranged to continuously detect the pressure in the to-be-detected gas cylinder, and when the gas is injected, an inlet of the to-be-detected gas cylinder is communicated with the gas outlet end of the gas filling pipeline through a connector; the first pressure gauge is arranged in the observation chamber and communicated with the pressure test end of the inflation pipeline, and the second pressure gauge is communicated with an inlet of the to-be-tested gas cylinder through the connector; and when the duration for keeping the pressure in the to-be-detected gas cylinder at the preset pressure reaches the preset duration, performing pressure relief to obtain the gas cylinder after pressure relief. According to the scheme, a certain amount of purified water is injected into the to-be-tested gas cylinder firstly, then gas is injected for pressure testing, and therefore the purposes that the pressurization rate is controllable, and meanwhile the safety of the gas cylinder at high pressure is guaranteed are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of pressure testing, and in particular to a method and device for pressure testing a gas cylinder. Background Art

[0002] Gas cylinders are storage containers in pressure vessels, and are sealed devices used to hold gas and bear a certain pressure. In the field of aerospace, due to the working environment and rocket load, the structure, pressure resistance, and wall thickness of gas cylinders need to be strictly controlled. Pressure tests are required before they are put into use to ensure the safety and reliability of the gas cylinders under the required working conditions. This requires testing of gas cylinders closer to the limit, with higher requirements for safety protection and accuracy.

[0003] Traditional pressure test methods mainly include water pressure test and air pressure test. Traditional water pressure test applies a certain pressure by injecting water into the gas cylinder to observe whether the gas cylinder has leakage, deformation and other problems to determine whether it meets the use requirements. Traditional water pressure test requires a lot of water resources, and because of the joint design, the filling process is time-consuming and labor-intensive. There is also a risk of water leakage. The pressurization rate is too fast, which can easily cause over-testing and increase the risk of explosion. Traditional air pressure test applies a certain pressure by injecting air into the gas cylinder. Although the pressurization rate is controllable, it is not suitable for rising to high pressure. Once the high-pressure air explodes, it is too dangerous. Summary of the invention

[0004] In view of this, an embodiment of the present invention provides a method and device for testing the pressure of a gas cylinder, so as to achieve a controllable pressurization rate and ensure the safety of the gas cylinder when it is under high pressure.

[0005] To achieve the above objectives, the embodiments of the present invention provide the following technical solutions:

[0006] A first aspect of an embodiment of the present invention discloses a pressure test method for a gas cylinder, the method comprising:

[0007] Injecting pure water into the gas cylinder to be tested until the ratio of the volume of the pure water in the gas cylinder to be tested to the total volume of the gas cylinder to be tested reaches a preset range;

[0008] Inject gas into the gas cylinder to be tested until the pressure in the gas cylinder to be tested reaches a preset pressure, wherein at least two pressure gauges with the same measuring range are provided to continuously detect the pressure in the gas cylinder to be tested, and when injecting gas, the inlet of the gas cylinder to be tested is detachably connected to the gas outlet end of the inflation pipe through a connector, the first pressure gauge is provided in the observation room and is connected to the pressure test end of the inflation pipe, and the second pressure gauge is connected to the inlet of the gas cylinder to be tested through a connector;

[0009] When the time period during which the pressure in the gas cylinder to be tested maintains the preset pressure reaches the preset time period, the gas cylinder to be tested is depressurized to obtain a depressurized gas cylinder.

[0010] Preferably, injecting gas into the gas cylinder to be tested until the pressure in the gas cylinder to be tested reaches a preset pressure comprises:

[0011] The inlet of the gas cylinder to be tested is detachably connected to the gas outlet of the gas charging pipe by using a connector;

[0012] Controlling a booster air pump connected to the air inlet end of the inflation pipe to inject gas into the gas cylinder to be tested at a speed of 1.5 to 2 MPa / min, and using the first pressure gauge to detect in real time to obtain a first pressure, and using the second pressure gauge to detect in real time to obtain a second pressure;

[0013] Whenever the first pressure increases by 10 MPa, the booster air pump is controlled to stop inflating and resume inflating after 10 seconds until the pressure in the gas cylinder to be tested reaches a preset pressure;

[0014] If the first pressure is not equal to the second pressure, the booster air pump is controlled to stop injecting gas into the gas cylinder to be tested, and the pressure of the gas cylinder to be tested is relieved.

[0015] Preferably, the method further comprises:

[0016] A camera is used to aim at the gas cylinder to be tested to take a picture, and the picture is transmitted in real time to a display device in the observation room for display.

[0017] Preferably, the method further comprises:

[0018] If the gas cylinder after depressurization is a qualified gas cylinder, point the nozzle of the qualified gas cylinder toward the ground, use an air gun to fill the nozzle of the qualified gas cylinder with gas for 3s to 5s, then remove the air gun, so that the pure water in the qualified gas cylinder is emptied;

[0019] Inject 500 ml of anhydrous ethanol into the qualified gas cylinder and shake the qualified gas cylinder;

[0020] Place the nozzle of the qualified gas cylinder toward the ground, and use an air gun to fill the nozzle of the qualified gas cylinder with gas for 3s to 5s, then remove the air gun to drain the anhydrous ethanol in the qualified gas cylinder;

[0021] Detecting the number of particles in the anhydrous ethanol discharged from the qualified gas cylinder;

[0022] If the particle quantity is greater than the particle quantity threshold, return to the step of injecting 500 ml of anhydrous ethanol into the qualified gas cylinder and shaking the qualified gas cylinder;

[0023] If the particle quantity is less than or equal to the particle quantity threshold, placing the qualified gas cylinder in the oven;

[0024] The oven was controlled to bake at 85° C. for 2 hours to obtain the cleaned qualified gas cylinder.

[0025] Preferably, the first pressure gauge and the second pressure gauge are pressure gauges with consistent range, graduation value and dial diameter, wherein the range is 50Mpa, the graduation value is 1Mpa, and the dial diameter is 120mm.

[0026] Preferably, the preset range includes: 3 / 4 to 4 / 5 interval.

[0027] Preferably, the preset pressure is 15 MPa or 30 MPa.

[0028] Preferably, the preset duration is 5 minutes.

[0029] Preferably, the gas includes: air.

[0030] A second aspect of an embodiment of the present invention discloses a pressure test device for a gas cylinder, the device comprising: a water injection device, an air filling pipeline, a first pressure gauge, a second pressure gauge and a connector;

[0031] The water injection device is detachably connected to the inlet of the gas cylinder to be tested, and is used to inject pure water into the gas cylinder to be tested until the ratio of the volume of the pure water in the gas cylinder to be tested to the total volume of the gas cylinder to be tested reaches a preset range;

[0032] The gas outlet end of the gas charging pipe is detachably connected to the inlet of the gas cylinder to be tested through the connector, so as to inject gas into the gas cylinder to be tested until the pressure in the gas cylinder to be tested reaches a preset pressure;

[0033] The first pressure gauge is arranged in the observation room and is connected to the pressure test end of the inflation pipe. The second pressure gauge is connected to the inlet of the gas cylinder to be tested through the connector, and is used to continuously detect the pressure in the gas cylinder to be tested. When the pressure in the gas cylinder to be tested maintains the preset pressure for a preset time, the gas cylinder to be tested is depressurized to obtain a depressurized gas cylinder.

[0034] Based on the above-mentioned embodiment of the present invention, a method and device for pressure testing a gas cylinder is provided. Pure water is injected into the gas cylinder to be tested until the ratio of the volume of the pure water in the gas cylinder to be tested to the total volume of the gas cylinder to be tested reaches a preset range; gas is injected into the gas cylinder to be tested until the pressure in the gas cylinder to be tested reaches a preset pressure, wherein at least two pressure gauges with the same range are provided to continuously detect the pressure in the gas cylinder to be tested. When injecting gas, the inlet of the gas cylinder to be tested is detachably connected to the gas outlet end of the inflation pipe through a connector, the first pressure gauge is provided in the observation room and connected to the pressure test end of the inflation pipe, and the second pressure gauge is connected to the inlet of the gas cylinder to be tested through a connector; when the pressure in the gas cylinder to be tested maintains the preset pressure for a preset time, the gas cylinder to be tested is depressurized to obtain a depressurized gas cylinder. In this solution, a certain amount of pure water is first injected into the gas cylinder to be tested, and then gas is injected for pressure testing, so as to achieve controllable pressurization rate and ensure the safety of the gas cylinder at high pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0036] Figure 1 A flow chart of a pressure test method for a gas cylinder disclosed in an embodiment of the present invention;

[0037] Figure 2 A schematic diagram of a connector disclosed in an embodiment of the present invention;

[0038] Figure 3 A flow chart of a gas cylinder cleaning method disclosed in an embodiment of the present invention;

[0039] Figure 4 This is a structural diagram of a pressure testing device disclosed in an embodiment of the present invention. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] In this application, the terms "comprises", "comprising" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element.

[0042] As can be seen from the background technology, traditional pressure test methods mainly include water pressure test and air pressure test. The traditional water pressure test applies a certain pressure to the gas cylinder by injecting water, and observes whether the gas cylinder has leakage, deformation and other problems to determine whether it meets the use requirements. The traditional water pressure test consumes a lot of water resources, and because of the joint design, the filling process is time-consuming and labor-intensive. There is also a risk of water leakage, and the pressurization rate is too fast, which is easy to cause over-testing and increase the risk of explosion. The traditional air pressure test applies a certain pressure to the gas cylinder by injecting air. Although the pressurization rate is controllable, it is not suitable for rising to high pressure. Once the high-pressure air explodes, it is too dangerous.

[0043] Therefore, an embodiment of the present invention discloses a method and device for pressure testing of gas cylinders. In this scheme, a certain amount of pure water is first injected into the gas cylinder to be tested, and then gas is injected for pressure testing to achieve controllable pressurization rate while ensuring the safety of the gas cylinder under high pressure.

[0044] like Figure 1 FIG. 1 is a flow chart of a method for pressure testing a gas cylinder disclosed in an embodiment of the present invention, comprising the following steps:

[0045] Step S101: pure water is injected into the gas cylinder to be tested until the ratio of the volume of the pure water in the gas cylinder to be tested to the total volume of the gas cylinder to be tested reaches a preset range.

[0046] In step S101, the gas cylinder to be tested is an aerospace gas cylinder with a capacity of 5L, a working pressure of 15Mpa, and a bursting pressure of 30Mpa.

[0047] The preset range includes: 3 / 4 to 4 / 5 interval, which not only ensures sufficient space to achieve precise control of air pressure, but also reduces the possible explosive power.

[0048] In the specific implementation process of step S101, the water outlet of the water injection device is detachably connected to the inlet of the gas cylinder to be tested, and pure water is injected into the gas cylinder to be tested until the ratio of the volume of pure water in the gas cylinder to be tested to the total volume of the gas cylinder to be tested reaches a preset range, and the connection between the water outlet of the water injection device and the inlet of the gas cylinder to be tested is disconnected.

[0049] It should be noted that there is no need to maintain airtightness during the water injection process. The purpose of water injection is to ensure the safety of the gas cylinder after the subsequent gas injection reaches high pressure, that is, to reduce the risk of accidental explosion during the gas pressure test.

[0050] Step S102: injecting gas into the gas cylinder to be tested until the pressure in the gas cylinder to be tested reaches a preset pressure.

[0051] In step S102, at least two pressure gauges with the same measuring range are set to continuously detect the pressure in the gas cylinder to be tested. When the gas is injected, the inlet of the gas cylinder to be tested is detachably connected to the gas outlet end of the inflation pipe through a connector. The first pressure gauge is set in the observation room and connected to the pressure test end of the inflation pipe, and the second pressure gauge is connected to the inlet of the gas cylinder to be tested through a connector.

[0052] Among them, the first pressure gauge and the second pressure gauge are pressure gauges with the same range, graduation value and dial diameter. The blasting pressure in this embodiment is required to be 30+2Mpa, so a pressure gauge with a range of 50Mpa, a graduation value of 1Mpa and a dial diameter of 120mm is selected to ensure the control of the pressure increase rate and accurate reading.

[0053] It should be noted that the second pressure gauge is for more accurate internal pressure of the reaction gas cylinder, and the first pressure gauge is set in the observation room, one is to facilitate observation by test personnel during debugging (because isolation is required during pressurization to ensure the safety of test personnel), and the other is to compare with the second pressure gauge to prevent errors.

[0054] Preferably, the preset pressure is equal to the working pressure of the gas cylinder 15 MPa or the bursting pressure 30 MPa.

[0055] It should be noted that each gas cylinder in the same batch is required to undergo a pressure test with a preset pressure of 15Mpa. After one pressure test is completed, one identification piece is randomly selected and subjected to at least 50 pressure tests with a preset pressure of 15Mpa to complete the fatigue test. The identification piece is then subjected to a pressure test with a preset pressure of 30Mpa to determine whether the performance of the gas cylinder under extreme conditions meets the design requirements.

[0056] Preferably, the gas injected into the gas cylinder to be tested can be air. If high precision is required, a gas insoluble in water can be selected.

[0057] The specific implementation process of step S102 includes the following steps:

[0058] Step S21: Using a connector, the inlet of the gas cylinder to be tested is detachably connected to the gas outlet end of the inflation pipe.

[0059] like Figure 2As shown, it is a schematic diagram of a connector disclosed in an embodiment of the present invention. The circled part in the figure is the connector, and an interface is reserved on the connector for connecting the first pressure gauge and the air outlet end of the inflation pipe.

[0060] Preferably, the connector is detachably connected to the inlet of the gas cylinder to be tested by bolts, wherein the connector is connected to the gas outlet end of the inflation pipe.

[0061] Among them, the bolt torque is set to ensure that the connection is securely fastened and the sealing meets the standards.

[0062] It should be noted that the inlet of the gas cylinder to be tested is detachably connected to the gas outlet end of the inflation pipe. After completing the pressure test of one gas cylinder, it is disassembled and the inlet of the next gas cylinder to be tested is detachably connected to the gas outlet end of the inflation pipe.

[0063] Step S22: Control the booster air pump connected to the air inlet end of the inflation pipe to inject gas into the gas cylinder to be tested at a speed of 1.5 to 2 MPa / min, and use the first pressure gauge to detect the first pressure in real time, and use the second pressure gauge to detect the second pressure in real time.

[0064] In step S22, the internal pressure of the gas cylinder is increased to a preset pressure at a speed of 1.5 to 2 MPa / min, which ensures that the gas cylinder structure will not be over-tested to affect product performance, and the speed will not be too slow to cause a waste of time efficiency.

[0065] Step S23: Whenever the first pressure increases by 10 MPa, the booster pump is controlled to stop inflating and resume inflating after 10 seconds until the pressure in the gas cylinder to be tested reaches a preset pressure.

[0066] In step S23, the pressure is maintained for 10 seconds for every 10 MPa during the pressure increase process. If air leakage or seepage occurs, the pressure is released immediately, and the connector, inflation pipe and bottle body are checked.

[0067] Preferably, a camera is used to aim at the gas cylinder to be tested to take a picture, and the picture is transmitted in real time to a display device in the observation room for display.

[0068] In the embodiment of the present invention, whether the gas cylinder is leaking during the pressure test is remotely observed, and the reading of the first pressure gauge is observed to ensure the safety of the test personnel.

[0069] Step S24: If the first pressure is not equal to the second pressure, the booster pump is controlled to stop injecting gas into the gas cylinder to be tested, and the pressure of the gas cylinder to be tested is relieved.

[0070] In step S24, during the inflation process, if the first pressure is not equal to the second pressure, it means that an error occurs in the pressure test process. Possible errors include: a damaged pressure gauge, a leak in the inflation pipe, etc.

[0071] Step S103: When the time period during which the pressure in the gas cylinder to be tested maintains the preset pressure reaches the preset time period, the gas cylinder to be tested is depressurized to obtain a depressurized gas cylinder.

[0072] In step S103, the preset time is 5 minutes, that is, the pressure is maintained for 5 minutes after reaching the set pressure. If leakage or seepage occurs, the pressure is released immediately, and the connector, inflation pipe and bottle body are checked.

[0073] Preferably, a camera is used to shoot the gas cylinder to be tested, and the shot image is transmitted in real time to a display device in the observation room for display, so as to remotely observe whether the gas cylinder is leaking during the pressure test and observe the reading of the first pressure gauge to ensure the safety of the test personnel.

[0074] It should be noted that after obtaining the depressurized gas cylinder, the test personnel will inspect the bottle body, focusing on the joints and welding points. If there is no abnormal phenomenon such as leakage, sweating, orange peel, bulging, collapse, deformation, etc., it is qualified.

[0075] In one embodiment, after obtaining the qualified gas cylinder, it needs to be cleaned, such as Figure 3 FIG. 1 is a flow chart of a gas cylinder cleaning method disclosed in an embodiment of the present invention, which specifically includes the following steps:

[0076] Step S301: If the gas cylinder after pressure relief is a qualified gas cylinder, point the nozzle of the qualified gas cylinder toward the ground, and use an air gun to fill the nozzle of the qualified gas cylinder with air for 3s to 5s, then remove the air gun to drain the pure water in the qualified gas cylinder.

[0077] In step S301, after the test is passed and a qualified gas cylinder is obtained, the connector is removed, the nozzle of the gas cylinder is pointed downward at the water tank, and an air gun is used to block the nozzle of the gas cylinder from bottom to top to fill with air for 3-5 seconds, and the liquid in the bottle is quickly drained by compressed air until the nozzle of the gas cylinder cannot drain any liquid even when it is pointed vertically downward. This method can drain the liquid simply and quickly, and can also discharge some tiny foreign matter together through pressure.

[0078] Among them, the nozzle of the gas cylinder is the inlet of the gas cylinder when inflating, and the liquid refers to pure water.

[0079] Step S302: inject 500 ml of anhydrous ethanol into the qualified gas cylinder and shake the qualified gas cylinder.

[0080] Step S303: direct the nozzle of the qualified gas cylinder toward the ground, and use an air gun to fill the nozzle of the qualified gas cylinder with gas for 3s to 5s, then remove the air gun to drain the anhydrous ethanol in the qualified gas cylinder.

[0081] In step S303, after the gas cylinder is emptied, some pure water will still be attached inside. It is necessary to inject about 500 ml of anhydrous ethanol and shake it to clean the bottle and replace the pure water.

[0082] It should be noted that generally one tenth of the volume of the gas cylinder needs to be injected with anhydrous ethanol. In the embodiment of the present invention, the aerospace gas cylinder is 5L, so about 500ml of anhydrous ethanol needs to be injected.

[0083] It can be understood that the discharge method of anhydrous ethanol is the same as the discharge method of pure water in step S301, except that the objects of discharge are different, so they can be referred to each other.

[0084] Step S304: Detect the number of particles in the anhydrous ethanol discharged from the qualified gas cylinder.

[0085] Generally speaking, injecting anhydrous ethanol once cannot achieve the cleaning goal, so it is preferred to repeat step S303 five times before starting step S304 to reduce unnecessary work.

[0086] It should be noted that the particle count refers to the number of impurities and dust particles in every 100 ml of anhydrous ethanol. There are special testing standards and testing instruments. In the testing standards, the particle size is divided into multiple ranges. Each range is set with a corresponding particle count threshold. The particle count corresponding to each range needs to meet the corresponding particle count threshold.

[0087] For example, the detection standard adopts the Q / W925A-D2 detection standard, and its particle size range and its corresponding particle number threshold are shown in the following table:

[0088]

[0089] Step S305: If the number of particles is greater than the particle number threshold, the process returns to step S302.

[0090] Step S306: If the number of particles is less than or equal to the particle number threshold, the qualified gas cylinder is placed in an oven and the oven is controlled to bake at 85° C. for 2 hours to obtain a cleaned qualified gas cylinder.

[0091] In step S306, the gas cylinder is placed in an oven and baked at 85°C for 2 hours to evaporate the residual ethanol inside. After baking, the gas cylinder nozzle is immediately sealed and the outside is cleaned and packaged.

[0092] Based on a pressure test method for a gas cylinder disclosed in the above-mentioned embodiment of the present invention, pure water is injected into the gas cylinder to be tested until the ratio of the volume of pure water in the gas cylinder to be tested to the total volume of the gas cylinder to be tested reaches a preset range; gas is injected into the gas cylinder to be tested until the pressure in the gas cylinder to be tested reaches a preset pressure, wherein at least two pressure gauges with the same range are provided to continuously detect the pressure in the gas cylinder to be tested, and when injecting gas, the inlet of the gas cylinder to be tested is detachably connected to the gas outlet end of the inflation pipe through a connector, the first pressure gauge is provided in the observation room and connected to the pressure test end of the inflation pipe, and the second pressure gauge is connected to the inlet of the gas cylinder to be tested through a connector; when the pressure in the gas cylinder to be tested maintains the preset pressure for a preset time, the gas cylinder to be tested is depressurized to obtain a depressurized gas cylinder. In this scheme, a certain amount of pure water is first injected into the gas cylinder to be tested, and then gas is injected for pressure testing, so as to achieve controllable pressurization rate and ensure the safety of the gas cylinder at high pressure.

[0093] Corresponding to the pressure test method of a gas cylinder disclosed in the above embodiment of the present invention, as Figure 4 , which is a structural diagram of a pressure testing device disclosed in an embodiment of the present invention, comprising: a water injection device 1, an air filling pipe 2, a first pressure gauge 3, a second pressure gauge 4 and a connector 5.

[0094] The water injection device 1 is detachably connected to the inlet of the gas cylinder to be tested, and is used to inject pure water into the gas cylinder to be tested until the ratio of the volume of the pure water in the gas cylinder to be tested to the total volume of the gas cylinder to be tested reaches a preset range;

[0095] The gas outlet end of the gas charging pipe 2 is detachably connected to the inlet of the gas cylinder to be tested through the connector 5, and is used to inject gas into the gas cylinder to be tested until the pressure in the gas cylinder to be tested reaches a preset pressure.

[0096] The first pressure gauge 3 is arranged in the observation room and connected with the pressure test end of the inflation pipe 2. The second pressure gauge 4 is connected with the inlet of the gas cylinder to be tested through the connector 5, and is used to continuously detect the pressure in the gas cylinder to be tested. When the pressure in the gas cylinder to be tested maintains a preset pressure for a preset time, the gas cylinder to be tested is depressurized to obtain a depressurized gas cylinder.

[0097] In one embodiment, the pressure testing device also includes a camera and a display device arranged in an observation room. The camera is connected to the display device and is used to use the camera to shoot the gas cylinder to be tested, and transmit the shooting image to the display device in the observation room in real time for display.

[0098] Based on a pressure testing device for a gas cylinder disclosed in the above-mentioned embodiment of the present invention, pure water is injected into the gas cylinder to be tested until the ratio of the volume of pure water in the gas cylinder to be tested to the total volume of the gas cylinder to be tested reaches a preset range; gas is injected into the gas cylinder to be tested until the pressure in the gas cylinder to be tested reaches a preset pressure, wherein at least two pressure gauges with the same range are provided to continuously detect the pressure in the gas cylinder to be tested, and when injecting gas, the inlet of the gas cylinder to be tested is detachably connected to the gas outlet end of the inflation pipe through a connector, the first pressure gauge is provided in the observation room and connected to the pressure test end of the inflation pipe, and the second pressure gauge is connected to the inlet of the gas cylinder to be tested through a connector; when the pressure in the gas cylinder to be tested maintains the preset pressure for a preset time, the gas cylinder to be tested is depressurized to obtain a depressurized gas cylinder. In this solution, a certain amount of pure water is first injected into the gas cylinder to be tested, and then gas is injected for pressure testing, so as to achieve controllable pressurization rate and ensure the safety of the gas cylinder at high pressure.

[0099] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can refer to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system or system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can refer to the partial description of the method embodiment. The system and system embodiments described above are merely schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without creative work.

[0100] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0101] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A pressure test method for a gas cylinder, characterized in that: The method comprises: Injecting pure water into the gas cylinder to be tested until the ratio of the volume of the pure water in the gas cylinder to be tested to the total volume of the gas cylinder to be tested reaches a preset range; Inject gas into the gas cylinder to be tested until the pressure in the gas cylinder to be tested reaches a preset pressure, wherein at least two pressure gauges with the same measuring range are provided to continuously detect the pressure in the gas cylinder to be tested, and when injecting gas, the inlet of the gas cylinder to be tested is detachably connected to the gas outlet end of the inflation pipe through a connector, the first pressure gauge is provided in the observation room and is connected to the pressure test end of the inflation pipe, and the second pressure gauge is connected to the inlet of the gas cylinder to be tested through a connector; When the time period during which the pressure in the gas cylinder to be tested maintains the preset pressure reaches the preset time period, the gas cylinder to be tested is depressurized to obtain a depressurized gas cylinder.

2. The method according to claim 1, characterized in that The step of injecting gas into the gas cylinder to be tested until the pressure in the gas cylinder to be tested reaches a preset pressure includes: The inlet of the gas cylinder to be tested is detachably connected to the gas outlet of the gas charging pipe by using a connector; Controlling a booster air pump connected to the air inlet end of the inflation pipe to inject gas into the gas cylinder to be tested at a speed of 1.5 to 2 MPa / min, and using the first pressure gauge to detect in real time to obtain a first pressure, and using the second pressure gauge to detect in real time to obtain a second pressure; Whenever the first pressure increases by 10 MPa, the booster air pump is controlled to stop inflating and resume inflating after 10 seconds until the pressure in the gas cylinder to be tested reaches a preset pressure; If the first pressure is not equal to the second pressure, the booster air pump is controlled to stop injecting gas into the gas cylinder to be tested, and the pressure of the gas cylinder to be tested is relieved.

3. The method according to claim 1, characterized in that The method further comprises: A camera is used to aim at the gas cylinder to be tested to take a picture, and the picture is transmitted in real time to a display device in the observation room for display.

4. The method according to claim 1, characterized in that: The method further comprises: If the gas cylinder after depressurization is a qualified gas cylinder, point the nozzle of the qualified gas cylinder toward the ground, and use an air gun to fill the nozzle of the qualified gas cylinder with gas for 3s to 5s, then remove the air gun, so that the pure water in the qualified gas cylinder is emptied; Inject 500 ml of anhydrous ethanol into the qualified gas cylinder and shake the qualified gas cylinder; Place the nozzle of the qualified gas cylinder toward the ground, and use an air gun to fill the nozzle of the qualified gas cylinder with gas for 3s to 5s, then remove the air gun to drain the anhydrous ethanol in the qualified gas cylinder; Detecting the number of particles in the anhydrous ethanol discharged from the qualified gas cylinder; If the particle quantity is greater than the particle quantity threshold, return to the step of injecting 500 ml of anhydrous ethanol into the qualified gas cylinder and shaking the qualified gas cylinder; If the particle quantity is less than or equal to the particle quantity threshold, placing the qualified gas cylinder in the oven; The oven was controlled to bake at 85° C. for 2 hours to obtain the cleaned qualified gas cylinder.

5. The method according to any one of claims 1 to 4, characterized in that: The first pressure gauge and the second pressure gauge are pressure gauges with the same range, graduation value and dial diameter, wherein the range is 50 MPa, the graduation value is 1 MPa, and the dial diameter is 120 mm.

6. The method according to any one of claims 1 to 4, characterized in that: The preset range includes: 3 / 4 to 4 / 5 interval.

7. The method according to any one of claims 1 to 4, characterized in that: The preset pressure is 15Mpa or 30Mpa.

8. The method according to any one of claims 1 to 4, characterized in that: The preset duration is 5 minutes.

9. The method according to any one of claims 1 to 4, characterized in that: The gas includes: air.

10. A pressure test device for a gas cylinder, characterized in that: The device comprises: a water injection device, an air filling pipeline, a first pressure gauge, a second pressure gauge and a connector; The water injection device is detachably connected to the inlet of the gas cylinder to be tested, and is used to inject pure water into the gas cylinder to be tested until the ratio of the volume of the pure water in the gas cylinder to be tested to the total volume of the gas cylinder to be tested reaches a preset range; The gas outlet end of the gas charging pipe is detachably connected to the inlet of the gas cylinder to be tested through the connector, so as to inject gas into the gas cylinder to be tested until the pressure in the gas cylinder to be tested reaches a preset pressure; The first pressure gauge is arranged in the observation room and is connected to the pressure test end of the inflation pipe. The second pressure gauge is connected to the inlet of the gas cylinder to be tested through the connector, and is used to continuously detect the pressure in the gas cylinder to be tested. When the pressure in the gas cylinder to be tested maintains the preset pressure for a preset time, the gas cylinder to be tested is depressurized to obtain a depressurized gas cylinder.

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