Double-vacuum degassing sample tube and use method thereof

Abstract

The invention discloses a double-vacuum degassing sample tube and a using method thereof, and relates to the technical field of sample analysis experiment equipment.The double-vacuum degassing sample tube comprises a pit furnace, an outer tube, an inner tube, a three-way tube, a tube penetrating connector, a first sealing connector and a second sealing connector, the outer tube is detachably arranged in the pit furnace, and the three-way tube is arranged at the upper end of the outer tube in a sleeving mode; a pipe penetrating connector is detachably arranged at the upper end of the three-way pipe, an inner pipe is arranged in the pipe penetrating connector in a penetrating mode, a gap is reserved between the outer wall of the inner pipe and the inner wall of the outer pipe, and the inner pipe and the three-way pipe are movably arranged in a penetrating mode. The device has the advantages of low permeability, low cost and long-term airtight stability, can meet the high-precision gas analysis requirements of earth deep rocks, moon samples and the like, and is compact in structure, economical in cost, simple and convenient to operate, small in size and wide in applicable experiment range and variety.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sample analysis experiment equipment, in particular to a double-vacuum degassing sample tube and a use method thereof. BACKGROUND

[0002] In the field of earth science and planetary science research, the geochemical characteristics of gases trapped in rocks and minerals are crucial for analyzing geological history and celestial evolution. These gases carry key information about the physical and chemical environment of sample crystallization and formation stage, as well as the source of matter, which is invaluable for revealing the mechanism of fluid action in the Earth's interior and exploring the formation and evolution of planets.

[0003] In the prior art, the sample tube used in the thermal desorption gas method includes a conventional sodium-calcium glass tube, a single-layer high-purity quartz glass tube, a gold-plated quartz glass tube, and a double-vacuum tube composed of molybdenum or tantalum. The thermal expansion coefficient of the conventional sodium-calcium glass tube is as high as 9x10 -6 / ℃ at temperatures above 550℃, and micro-cracks expand significantly, with a bearing temperature not higher than 600℃; although the single-layer high-purity quartz glass tube has a relatively low overall permeability, the gas permeability rises sharply at >750℃; the gold-plated quartz tube has a significant inhibitory effect on the permeation of large molecules such as Ar, but its blocking ability for small molecules such as H2 and He is limited; the double-vacuum furnace tube composed of molybdenum or tantalum is prone to react with active gases at high temperatures, which is not suitable for gas component analysis, and is easily damaged, resulting in high experimental costs. The existing various types of sample tubes cannot simultaneously meet the requirements of low permeability, low cost, and long-term airtight stability under high-temperature conditions, and are difficult to meet the high-precision analysis requirements of gases in deep earth samples and lunar samples.

[0004] To solve the above problems, a double-vacuum degassing sample tube and a use method thereof are provided. SUMMARY

[0005] The present application provides a double-vacuum degassing sample tube and a use method thereof to solve the problem that the existing various types of sample tubes cannot simultaneously meet the requirements of low permeability, low cost, and long-term airtight stability under high-temperature conditions, and are difficult to meet the high-precision analysis requirements of gases in deep earth samples and lunar samples.

[0006] The technical scheme adopted by the present application is as follows: a base platform, a muffle furnace, a detection device, an outer tube, an inner tube, a tee joint, a first sealing joint, and a second sealing joint are included; The detection device includes a vacuum pump and a detection probe provided by the detection device; The outer tube is detachably arranged in the muffle furnace, and the base platform for controlling temperature is arranged at the bottom of the muffle furnace; The upper end of the outer tube is sleeved with the tee joint, and the upper end of the tee joint is detachably provided with the pipe connector; The lower end of the tee pipe and the upper end of the furnace are detachably connected; An inner pipe is arranged in the through pipe joint, and the inner pipe is detachably arranged in the outer pipe; A sample to be detected is detachably arranged in the inner pipe, and a detection probe is detachably arranged in the inner pipe, and the detection probe is detachably connected with the sample to be detected; A gap is left between the outer wall of the inner pipe and the inner wall of the outer pipe; An branch pipe is arranged in communication with the middle end of the tee pipe, and the branch pipe is arranged in communication with the gap; The inner pipe and the tee pipe are movably arranged in communication; An first sealing joint is detachably arranged in communication with the outer end of the branch pipe; A second sealing joint is detachably arranged in communication with the top end of the inner pipe; The other end of the first sealing joint is detachably arranged with an external vacuum pump through a vacuum hose; The other end of the second sealing joint is arranged in communication with a vacuum pump of the detection device.

[0007] Further, the outer pipe and the inner pipe are products of the same batch; The outer pipe and the inner pipe are made of high-purity quartz glass with a purity of greater than or equal to 99.9%.

[0008] Further, the total length of the inner pipe is 30 cm; The outer diameter of the inner pipe is 6.4 mm, and the outer diameter of the outer pipe is 10 mm; The thickness of the gap is 1.5 mm; A first O-shaped sealing ring is arranged between the outer pipe and the tee pipe, a second O-shaped sealing ring is arranged between the through pipe joint and the tee pipe, and a third O-shaped sealing ring is arranged between the through pipe joint and the inner pipe.

[0009] Further, the first O-shaped sealing ring, the second O-shaped sealing ring, and the third O-shaped sealing ring are fluororubber O-shaped rings.

[0010] Further, the first sealing joint, the second sealing joint, and the through pipe joint are made of 316L stainless steel.

[0011] Further, the gap can be filled with inert gas.

[0012] Further, a vacuum gauge is arranged in the first sealing joint, and the vacuum gauge is electrically connected with an external display device.

[0013] According to another aspect of the present application, a use method of the double-vacuum degassing sample pipe is provided, comprising the following steps: Step one: crush the rock sample to a particle size of <1mm and weigh it, and for lunar samples, it needs to be processed in an inert glove box; Step two: check the integrity of the inner tube, outer tube, tube connector, tee tube, first sealing connector and second sealing connector, and ensure that there is no damage and no oxidation; Step three: connect the inner tube with the tube connector, connect the inner tube with the second sealing connector, connect the outer tube with the lower end of the tee tube, coaxially place the inner tube into the outer tube, and connect the lower end of the tube connector with the upper end of the tee tube, at this time, the annular gap is formed between the inner tube and the outer tube, connect the first sealing connector on the tube, and connect the first sealing connector with the external vacuum pump through the vacuum hose, initially connect the vacuum pump on the detection device with the second sealing connector; Step four: wipe the components with anhydrous ethanol, pre-treat the inner tube and outer tube in an environment of 150 DEG C using a muffle furnace, turn on the external vacuum pump connected with the first sealing connector and the switch for controlling the start and stop of the vacuum pump on the detection device, and vacuumize the annular gap and the inner tube in an environment of 150 DEG C for 15 minutes to remove residual gas; Step five: open the second sealing connector on the inner tube, and place the crushed sample into the sample placement area from the upper part of the inner tube, the sample placement area is at the bottom of the inner tube, and the lower surface of the inner tube can be marked to avoid overfilling, if the sample is a lunar sample, the inner tube can be disassembled and connected to the outer tube through the transition cabin into the inert glove box, and after the sample is placed, the inert material plug can be used for temporary sealing; Step six: connect the second sealing connector with the inner tube again, and make the detection probe in the detection device contact with the sample in the bottom of the inner tube; Step seven: turn on the external vacuum pump connected with the first sealing connector again, vacuumize the annular gap first, then turn on the start and stop switch of the vacuum pump on the detection device, vacuumize the inner tube, and then perform 10-minute pressure holding leak detection, after ten minutes, when the air tightness is qualified, the inner tube is vacuumized to high vacuum or ultrahigh vacuum; Step eight: place the outer tube into the lower muffle furnace, and heat the muffle furnace according to the experimental procedure and collect the gas in the inner tube; Step nine: after the experiment is completed, turn off the muffle furnace, and after the inner tube and the outer tube are cooled to room temperature, slowly release the inner tube and the outer tube to atmospheric pressure in sequence; Step ten: disassemble the inner tube and the outer tube, clean the sample residues, and dry store the cleaned components.

[0014] Advantages of the present application: The inner tube and the outer tube in the application are made of high-purity quartz glass, have low thermal expansion coefficient, are stable in structure at high temperature, reduce the generation of micro-cracks caused by thermal expansion and cold contraction, and ensure the air tightness, the application adopts a double-vacuum structure, the vacuum layer between the outer tube and the inner tube significantly reduces the concentration gradient driving force of gas diffusion, increases the diffusion path length, and effectively inhibits gas permeation in the whole temperature zone, the application adopts a double-vacuum structure, the vacuum layer between the outer tube and the inner tube significantly reduces the concentration gradient driving force of gas diffusion, increases the diffusion path length, and effectively inhibits gas permeation in the whole temperature zone, the inner tube in direct contact with the sample is not a metal tube, has excellent chemical inertness at high temperature, has zero reaction and zero pollution with rock samples and the like, and is especially suitable for trace gas component analysis.

[0015] In addition to the purposes, features and advantages described above, the application has other purposes, features and advantages, which will be described in further detail below with reference to the drawings. BRIEF DESCRIPTION OF DRAWINGS

[0016] The accompanying drawings, which form a part of this application, are included to provide a further understanding of the application, illustrate the preferred embodiments of the application, and assist in the explanation of the application. It will be appreciated that the drawings are only meant as illustrative and are not meant to limit the scope of the application as set forth in the claims.

[0017] Fig. 1 It is a schematic diagram of the overall structure of the application; Fig. 2 It is a schematic diagram of the overall structure of the application;

[0018] Reference signs: 1 is a base platform, 2 is a pit furnace, 3 is an outer tube, 4 is an inner tube, 5 is a pipe joint, 6 is a tee pipe, 7 is a first sealing joint, and 8 is a second sealing joint; 601 is a pipe. DETAILED DESCRIPTION

[0019] In order to make the purposes, technical solutions and advantages of the application clearer, the application will be further described in detail below with reference to the drawings and examples. It should be understood that the specific examples described herein are only used to explain the application and are not used to limit the application.

[0020] In the description of the application, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only used to facilitate the description of the application and simplify the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the application.

[0021] REFERENCE Figs. 1-2A double vacuum degassing sample tube comprises a base platform 1, a muffle furnace 2, a detection device, further comprises an outer tube 3, an inner tube 4, a tee pipe 6, a pipe joint 5, a first sealing joint 7, and a second sealing joint 8; The detection device comprises a vacuum pump and a detection probe; The outer tube 3 is detachably installed in the muffle furnace 2, the base platform 1 for controlling temperature is installed at the bottom of the muffle furnace 2, the muffle furnace 2 is used for heating the outer tube 3, the muffle furnace 2 can adjust the temperature during the heating degassing experiment, and the highest temperature can reach 1200 DEG C, which can adapt to the high-temperature melting experiment of deep earth rock and the thermal degassing requirement of lunar samples, and a gap of 2-4 mm is reserved between the furnace tube of the muffle furnace 2 and the outer tube 3, so that the outer tube 3 is conveniently put in; The upper end of the outer tube 3 is provided with the tee pipe 6, and the upper end of the tee pipe 6 is detachably provided with the pipe joint 5; The lower end of the tee pipe 6 is detachably connected with the upper end of the muffle furnace 2; The inner tube 4 is detachably installed in the outer tube 3, and the inner tube 4 is used for placing experimental samples; the samples in the inner tube 4 need to be ensured to be completely in the furnace tube when the outer tube 3 is put into the furnace tube of the muffle furnace 2, so as to ensure that the temperature fluctuation of the sample heating interval is less than or equal to ± 2 DEG C; The sample to be detected is detachably arranged in the inner tube 4, the detection device is detachably installed in the inner tube 4, and the detection device is detachably connected with the sample to be detected; the detection device is used for real-time mastering of sample property information, and the detection device comprises a vacuum pump and a detection probe; the part in contact with the sample to be detected is the detection probe; the vacuum pump and the detection probe are controlled to start and stop through an external control program; during the experiment, the output port of the vacuum pump of the detection device is connected with the second sealing joint 8 described below, and no additional vacuum pump is needed; A gap is reserved between the outer wall of the inner tube 4 and the inner wall of the outer tube 3; The middle end of the tee pipe 6 is communicated and provided with a branch pipe 601, the branch pipe 601 and the gap are communicated, and the branch pipe 601 and the first sealing joint 7 and the inner tube 4 and the second sealing joint 8 are all connected through a U-Torr sealing method suitable for repeatedly disconnecting and reconnecting in a vacuum system; the principle is that a carbon fluoride O-shaped ring is deformed through the fastening effect of a knurled nut to form a reliable seal; this design allows the joint to be repeatedly disassembled in the vacuum pressure system and still maintain stable sealing performance; The inner tube 4 and the tee pipe 6 are movably and penetratively arranged; The outer end of the branch pipe 601 is detachably and communicatively provided with the first sealing joint 7; The top end of the inner tube 4 is detachably and communicatively provided with the second sealing joint 8; The other end of the first sealing joint 7 is detachably provided with an external vacuum pump through a vacuum hose; The other end of the second sealing joint 8 is in communication with a vacuum pump provided in the detection device. The detection device is a gas analyzer, which has the same principle as a mass spectrometer. The output port of the detection device is provided with a matching vacuum pump and a detection probe, which works synchronously with the gas analyzer and does not need an additional vacuum pump for vacuumizing.

[0022] The outer tube 3 and the inner tube 4 are products of the same batch; The outer tube 3 and the inner tube 4 are made of high-purity quartz glass with a purity of ≥99.9%, which ensures that the outer tube 3 and the inner tube 4 have the same physical parameters such as thermal expansion coefficient, thereby ensuring the accuracy of the experiment.

[0023] The total length of the inner tube 4 is 30 cm, and the overall volume is reduced by more than 80% compared with the previous micro double vacuum furnace tube; The outer diameter of the inner tube 4 is 6.4 mm, and the outer diameter of the outer tube 3 is 10 mm; The thickness of the gap is 1.5 mm; The first O-shaped sealing ring is installed between the outer tube 3 and the three-way tube 6, the second O-shaped sealing ring is installed between the pipe penetrating joint 5 and the three-way tube 6, and the third O-shaped sealing ring is installed between the pipe penetrating joint 5 and the inner tube 4.

[0024] The first O-shaped sealing ring, the second O-shaped sealing ring and the third O-shaped sealing ring are all fluorine rubber O-shaped rings, which are necessary components in the U-Torr sealing method and are prior art, and will not be described here.

[0025] The first sealing joint 7, the second sealing joint 8 and the pipe penetrating joint 5 are all made of 316L stainless steel, which can adapt to the experimental environment in terms of corrosion resistance, sealing performance and high temperature stability.

[0026] The gap can be filled with inert gas to facilitate heat transfer and isolate air. It should be noted that this component cannot be included in the test. If dynamic monitoring of vacuum degree change is required, a vacuum gauge described later can be used.

[0027] The vacuum gauge is installed in the first sealing joint 7, and the vacuum gauge and the external display device are electrically connected, which can record the pressure data of the annular space in real time and provide a quantitative basis for the stability of the experiment.

[0028] The operation method of the double vacuum degassing sample tube comprises the following steps: Step one: crush the rock sample to a particle size of <1 mm and weigh it. The lunar sample needs to be processed in an inert glove box; Step two: check the integrity of the inner tube 4, the outer tube 3, the pipe penetrating joint 5, the three-way tube 6, the first sealing joint 7 and the second sealing joint 8 to ensure that there is no damage and no oxidation; Step three: connect the inner tube 4 with the through pipe joint 5, connect the top end of the inner tube 4 with the second sealing joint 8, connect the outer tube 3 with the lower end of the three-way pipe 6, coaxially place the inner tube 4 into the outer tube 3, and connect the lower end of the through pipe joint 5 with the upper end of the three-way pipe 6, at this time, the annular gap is formed between the inner tube 4 and the outer tube 3, connect the first sealing joint 7 on the branch pipe 601, and connect the first sealing joint 7 with the external vacuum pump through the vacuum hose, initially connect the vacuum pump on the detection device with the second sealing joint 8; Step four: wipe the components with anhydrous ethanol, pre-treat the inner tube 4 and the outer tube 3 in the environment of 150℃ using the muffle furnace 2, open the external vacuum pump connected with the first sealing joint 7 and the switch for controlling the start and stop of the vacuum pump on the detection device, and vacuumize the annular gap and the inner tube 4 in the environment of 150℃ for 15 minutes to remove residual gas, in the process of cleaning and degassing the glass tube, selecting the temperature of 150℃ can ensure the degassing effect, material stability and operation safety, 150℃ is commonly used in gas detection experiments, and heating and vacuumizing at this temperature can ensure that water, organic matter and other gases in the glass tube are completely removed, thereby increasing the accuracy of the experiment; Step five: open the second sealing joint 8 on the inner tube 4, and place the crushed sample into the sample placement area from the upper part of the inner tube 4, the sample placement area is at the bottom of the inner tube 4, and the lower surface of the inner tube 4 can be marked to avoid overfilling, if the sample is a lunar sample, the inner tube 4 can be removed and placed into the inert glove box through the transition cabin, and after the sample is placed, the inert material plug can be used for temporary sealing, and then the inner tube 4 is connected to the outer tube 3; Step six: connect the second sealing joint 8 with the inner tube 4 again, and make the detection probe in the detection device contact with the sample at the bottom of the inner tube 4, if the sample is a lunar sample, open the inert material plug before connecting the inner tube 4 with the second sealing joint 8, and then quickly connect the second sealing joint 8 with the inner tube 4, since the opening of the inert material plug to the completion of the connection belongs to “instantaneous operation”, the actual contact time of the lunar sample with the air is very short, which is much shorter than the time for triggering the significant oxidation reaction of the lunar sample, so as to not affect the experimental results; Step seven: open the external vacuum pump connected with the first sealing joint 7 again, vacuumize the annular gap first, then open the switch for controlling the start and stop of the vacuum pump on the detection device, vacuumize the inner tube 4, and then perform pressure maintaining and leak detection for 10 minutes, after ten minutes, if the air tightness is qualified, the inner tube 4 is vacuumized to high vacuum or ultra-high vacuum, the qualified standard of the pressure maintaining and leak detection is that the vacuum degree changes by less than or equal to a preset threshold within ten minutes, the judgment of the pressure maintaining and leak detection can be performed by a vacuum gauge, if the tube wall of the inner tube 4 is broken, the air pressure in the annular gap will be larger, the pressure change value will be captured by the vacuum gauge and displayed on the external display device, it should be noted that since the inner tube 4 and the outer tube 3 belong to the same batch of products, they need to be replaced synchronously when being replaced; Step eight: Put the outer tube 3 into the lower furnace 2, and heat the furnace 2 according to the experimental procedure and collect the gas in the inner tube 4, the gas released by the sample after heating will touch the detection probe in the detection device through the inner tube 4, and the gas is analyzed through the detection probe, which is usually a gas analyzer, and the heating temperature and time can be determined according to different experimental purposes and samples. The "experimental procedure" here refers to a kind of geochemical experiment using the device. The "experimental procedure" also includes the pre-treatment of vacuumizing the inner tube 4, which is usually vacuumized for another hour at 50℃. Different experiments require different vacuumizing conditions, which do not conflict with the pre-treatment of vacuumizing in step four; Step nine: After the experiment is completed, turn off the furnace 2, and slowly release the gas in the inner tube 4 and the outer tube 3 to normal pressure after they are cooled to room temperature; Step ten: disassemble the inner tube 4 and the outer tube 3, clean the sample residue, and dry the cleaned parts for storage.

[0029] The implementation method of the present application: The rock sample is crushed to a particle size of <1mm and weighed, and the lunar sample needs to be treated in an inert glove box; Check the integrity of the inner tube 4, the outer tube 3, the tube connector 5, the tee tube 6, the first sealing connector 7 and the second sealing connector 8 to ensure that there is no damage and no oxidation; Connect the inner tube 4 with the tube connector 5, connect the outer tube 3 with the lower end of the tee tube 6, and connect the inner tube 4 coaxially into the outer tube 3, and connect the lower end of the tube connector 5 with the upper end of the tee tube 6. At this time, an annular gap is formed between the inner tube 4 and the outer tube 3. Connect the first sealing connector 7 on the tube 601, and connect the first sealing connector 7 with the external vacuum pump through the vacuum hose. Initially, connect the vacuum pump on the detection device with the second sealing connector 8; Use anhydrous ethanol to wipe the parts, use the furnace 2 to pre-treat the inner tube 4 and the outer tube 3 at 150℃, open the external vacuum pump connected with the first sealing connector 7 and the switch that controls the start and stop of the vacuum pump on the detection device, and vacuumize the annular gap and the inner tube 4 at 150℃ for 15 minutes to remove residual gas; Connect the second sealing connector 8 with the inner tube 4 again, and make the detection probe in the detection device contact the sample at the bottom of the inner tube 4; Open the external vacuum pump connected with the first sealing connector 7 again, vacuumize the annular gap first, then open the switch that controls the start and stop of the vacuum pump on the detection device, and vacuumize the inner tube 4. After that, carry out 10 minutes of pressure holding and leak detection. After ten minutes, if the air tightness is qualified, vacuumize the inner tube 4 to high vacuum or ultra-high vacuum; Put the outer tube 3 into the lower well furnace 2, and heat the well furnace 2 according to the experimental procedure and collect the gas in the inner tube 4, the gas released by the sample after heating will touch the detection probe in the detection device through the inner tube 4, and the gas is analyzed through the detection probe; After the experiment, the well furnace 2 is closed, and after the inner tube 4 and the outer tube 3 are cooled to room temperature, the inner tube 4 and the outer tube 3 are slowly degassed to normal pressure in sequence; Disassemble the inner tube 4 and the outer tube 3, clean the sample residue, and dry store after cleaning the parts.

[0030] In the present application, the inner tube and the outer tube are both made of high-purity quartz glass, which has low thermal expansion coefficient and stable structure at high temperature, reduces the generation of micro-cracks caused by thermal expansion and contraction, and ensures the air tightness. The present application adopts a double vacuum structure, which significantly reduces the concentration gradient driving force of gas diffusion between the outer tube and the inner tube, increases the diffusion path length, and effectively inhibits gas permeation in the whole temperature zone. The inner tube in the present application, which directly contacts the sample, is not a metal tube, and has excellent chemical inertness at high temperature, zero reaction and zero pollution with rock samples, and is especially suitable for trace and trace gas component analysis.

[0031] The above only describes the preferred embodiments of the present application and does not limit the present application. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A double vacuum degassed sample tube comprising a detection device, a base platform (1), a furnace (2), characterized in that: It also comprises an outer tube (3), a tee pipe (6), a pipe joint (5), a first sealing joint (7), and a second sealing joint (8); The detection device comprises a vacuum pump and a detection probe; The outer tube (3) is detachably arranged in the pit furnace (2), and the base platform (1) for controlling temperature is arranged at the bottom of the pit furnace (2); The upper end of the outer tube (3) is sleeved with the tee pipe (6), and the upper end of the tee pipe (6) is detachably provided with the pipe joint (5); The lower end of the tee pipe (6) is detachably connected with the upper end of the pit furnace (2); The inner tube (4) is arranged in the outer tube (3); The sample to be detected is arranged in the inner tube (4), and the detection probe is arranged in the inner tube (4) and detachably connected with the sample to be detected; The outer wall of the inner tube (4) and the inner wall of the outer tube (3) are spaced apart; The middle end of the tee pipe (6) is communicated with a branch pipe (601), and the branch pipe (601) is communicated with the gap; The inner tube (4) and the tee pipe (6) are movably arranged; The outer end of the branch pipe (601) is detachably connected with the first sealing joint (7); The top end of the inner tube (4) is detachably connected with the second sealing joint (8); The other end of the first sealing joint (7) is detachably provided with an external vacuum pump through a vacuum hose; The other end of the second sealing joint (8) is communicated with the vacuum pump of the detection device.

2. The dual vacuum degassed sample tube of claim 1, characterized by: The outer tube (3) and the inner tube (4) are products of the same batch; The outer tube (3) and the inner tube (4) are made of high-purity quartz glass with a purity of ≥99.9%.

3. The dual vacuum degassed sample tube of claim 1, wherein: The total length of the inner tube (4) is 30 cm; The outer diameter of the inner tube (4) is 6.4 mm, and the outer diameter of the outer tube (3) is 10 mm; The thickness of the gap is 1.5 mm; A first O-shaped sealing ring is arranged between the outer tube (3) and the tee pipe (6), a second O-shaped sealing ring is arranged between the pipe joint (5) and the tee pipe (6), and a third O-shaped sealing ring is arranged between the pipe joint (5) and the inner tube (4).

4. The dual vacuum-dégassed sample tube of claim 3, characterized by: The first O-shaped sealing ring, the second O-shaped sealing ring, and the third O-shaped sealing ring are all fluorine rubber O-shaped rings.

5. The dual vacuum degassed sample tube of claim 1, characterized by: The first sealing joint (7), the second sealing joint (8), and the pipe joint (5) are all made of 316L stainless steel.

6. The dual vacuum degassed sample tube of claim 1, characterized by: The gap can be filled with inert gas.

7. The dual vacuum degassed sample tube of claim 1, wherein: A vacuum gauge is arranged in the first sealing joint (7), and the vacuum gauge is electrically connected with an external display device.

8. A double vacuum degassed sample tube and method of use thereof, based on the double vacuum degassed sample tube of any one of claims 1 to 7, characterized by: The method comprises the following steps: Step one: crushing the rock sample to a particle size of <1 mm and weighing, and processing the lunar sample in an inert glove box; Step two: checking the integrity of the inner tube (4), the outer tube (3), the pipe joint (5), the tee pipe (6), the first sealing joint (7), and the second sealing joint (8) to ensure that they are not damaged and not oxidized. Step three: connect the inner tube (4) with the pipe connector (5), connect the inner tube (4) with the second sealing connector (8), connect the outer tube (3) with the lower end of the three-way pipe (6), coaxially place the inner tube (4) into the outer tube (3), and connect the lower end of the pipe connector (5) with the upper end of the three-way pipe (6), at this time, the annular gap is formed between the inner tube (4) and the outer tube (3), connect the first sealing connector (7) on the branch pipe (601), and connect the first sealing connector (7) with the external vacuum pump through the vacuum hose, initially connect the vacuum pump on the detection device with the second sealing connector (8); Step four: use anhydrous ethanol to wipe the components, use the muffle furnace (2) to pre-treat the inner tube (4) and the outer tube (3) at 150℃, open the external vacuum pump connected with the first sealing connector (7) and the switch controlling the start and stop of the vacuum pump on the detection device, and vacuumize the annular gap and the inner tube (4) at 150℃ for 15 minutes to remove residual gas; Step five: open the second sealing connector (8) on the inner tube (4), and put the crushed sample into the sample placement area from the upper part of the inner tube (4), the sample placement area is at the bottom of the inner tube (4), and the lower surface of the inner tube (4) can be marked to avoid overfilling, if the sample is a lunar sample, the inner tube (4) can be disassembled and connected to the outer tube (3) through the transition cabin; Step six: connect the second sealing connector (8) with the inner tube (4) again, and make the detection probe in the detection device extend into the bottom of the inner tube (4) to contact the sample; Step seven: open the external vacuum pump connected with the first sealing connector (7) again, vacuumize the annular gap first, then open the start and stop switch of the vacuum pump on the detection device to vacuumize the inner tube (4), and then perform 10-minute pressure holding leak detection, after ten minutes, when the air tightness is qualified, the inner tube (4) is extracted to high vacuum or ultra-high vacuum; Step eight: place the outer tube (3) into the lower muffle furnace (2), and heat the muffle furnace (2) according to the experimental procedure and collect the gas in the inner tube (4); Step nine: after the experiment is completed, turn off the muffle furnace (2), and after the inner tube (4) and the outer tube (3) are cooled to room temperature, slowly release the inner tube (4) and the outer tube (3) to normal pressure in sequence; Step ten: disassemble the inner tube (4) and the outer tube (3), clean the sample residues, and dry store the cleaned components.

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