A partial pressure mass spectrometer and positive pressure leak integrated calibration device and method

Abstract

This disclosure provides a comprehensive calibration device and method for a vacuum partial pressure mass spectrometer and a positive pressure leak. The device incorporates an inlet capillary. When calibrating a positive pressure leak with a high leakage rate, if the vacuum partial pressure mass spectrometer fails to start due to excessive pressure, the inlet capillary branch is opened, thereby reducing the gas pressure entering the mass spectrometry chamber to 10. ‑4 The Pa level ensures the normal operation of the vacuum partial pressure mass spectrometer. Furthermore, by combining the magnetically levitated rotor vacuum gauge installed on the vacuum partial pressure mass spectrometer, the calibration scheme provided by this invention allows for the calibration of the vacuum partial pressure mass spectrometer under vacuum conditions using the same equipment, based on the calibration of positive pressure leaks. This meets the comprehensive calibration requirements of positive pressure environments for gas composition analysis and positive pressure leak detection in the manned spaceflight field.

Description

Technical Field

[0001] This invention relates to the field of measurement technology, specifically to a dynamic flow method vacuum partial pressure mass spectrometer based on static expansion and a comprehensive calibration device and method for positive pressure leaks. Background Technology

[0002] In scenarios where positive pressure leaks are calibrated using a vacuum partial pressure mass spectrometer, only positive pressure leaks with low leak rates can currently be calibrated. If calibrating positive pressure leaks with high leak rates, the gas pressure entering the mass spectrometry analysis chamber is too high, exceeding 10... -4 A pressure of 10 Pa will cause the vacuum partial pressure mass spectrometer to malfunction. Therefore, a calibration device suitable for positive pressure leaks of various leak rates needs to be designed.

[0003] Furthermore, in the field of manned spaceflight, there is now a clear requirement for integrated calibration of gas composition analysis and positive pressure leak detection. Therefore, it is hoped that the designed positive pressure leak calibration device can simultaneously meet the calibration requirements of vacuum partial pressure mass spectrometers. Summary of the Invention

[0004] In view of this, the present invention provides a comprehensive calibration device and method for a vacuum partial pressure mass spectrometer and a positive pressure leak based on a dynamic flow method of static expansion, which can realize a comprehensive calibration scheme for calibrating a positive pressure leak under positive pressure conditions and calibrating a gas partial pressure mass spectrometer under vacuum conditions in one device.

[0005] To solve the above-mentioned technical problems, the present invention is implemented as follows.

[0006] A comprehensive calibration device for partial pressure mass spectrometer and positive pressure leak includes: a gas supply system, a positive pressure leak to be measured, a sample preparation chamber, a gas expansion chamber, a sample inlet capillary, a flow limiting orifice, a mass spectrometry analysis chamber, a vacuum partial pressure mass spectrometer, and a gas extraction system.

[0007] The gas supply system is connected to the inlet of the positive pressure leak via the eighth vacuum valve. The outlet of the positive pressure leak is connected to the inlet of the sample preparation chamber via the first vacuum valve. The eighth vacuum valve is further connected to the inlet of the sample preparation chamber via the seventh vacuum valve. The sample preparation chamber is used to prepare the standard gas required for the calibration of the positive pressure leak and the vacuum partial pressure mass spectrometer, as well as the gas accumulation during the calibration of the positive pressure leak. The outlet of the sample preparation chamber is connected to the inlet of the gas expansion chamber via the second vacuum valve. The gas in the sample preparation chamber expands to the gas expansion chamber by static expansion. The outlet of the gas expansion chamber is connected to the third vacuum valve. The third vacuum valve is directly connected to the flow-limiting orifice on one hand, and on the other hand, it is connected to the flow-limiting orifice via a fourth vacuum valve in series and the sample inlet capillary. The other end of the flow-limiting orifice is connected to the mass spectrometry analysis chamber. Depending on the leakage rate of the positive pressure leak, the gas pressure is reduced to an acceptable level for the vacuum partial pressure mass spectrometer by using the flow-limiting orifice alone or in conjunction with the sample inlet capillary before entering the mass spectrometry analysis chamber. The gas extraction system is connected to the mass spectrometry analysis chamber via the fifth vacuum valve.

[0008] The sample preparation chamber and the gas expansion chamber are respectively connected to a capacitive thin-film vacuum gauge for measuring the gas pressure inside the chamber; the mass spectrometry analysis chamber is connected to a vacuum partial pressure mass spectrometer and a magnetic levitation rotor vacuum gauge for measuring the gas partial pressure and vacuum level in the mass spectrometry analysis chamber, respectively.

[0009] Preferably, the device further includes a sixth vacuum valve, one end of which is connected to the pipeline between the eighth and seventh vacuum valves, and the other end is connected to the pumping system through the fifth vacuum valve.

[0010] This invention also provides a comprehensive calibration method for a partial pressure mass spectrometer and a positive pressure leak, employing the aforementioned calibration device. The method includes:

[0011] Positive pressure leak calibration includes the following steps:

[0012] Step A1: Using the gas supply system, helium gas at the first pressure is introduced into the positive pressure leak inlet through the eighth vacuum valve, and nitrogen gas at the second pressure is introduced into the positive pressure leak outlet through the eighth vacuum valve, the seventh vacuum valve and the first vacuum valve. The first pressure is greater than the second pressure.

[0013] Step A2: Under the action of pressure difference, the gas flows into the sample preparation chamber for gas accumulation. The accumulated gas expands into the gas expansion chamber. According to the pressure shown by the second capacitor thin film vacuum gauge, after the gas pressure change reaches the set value, the third vacuum valve is opened, and the gas enters the mass spectrometry analysis chamber through the flow-limiting orifice.

[0014] Step A3: Determine if the gas partial pressure mass spectrometer is open normally; if not, open the fourth vacuum valve and use the sample introduction capillary to restrict the flow of the accumulated gas again, then proceed to step A4; if it is open normally, proceed directly to step A4.

[0015] Step A4: Read the accumulated gas pressure P1 after the positive pressure leak using a gas partial pressure mass spectrometer;

[0016] Step A5: Close the first vacuum valve and introduce standard gas into the sample preparation chamber through the gas supply system; the standard gas enters the mass spectrometry analysis chamber through the pipeline between the sample preparation chamber and the mass spectrometry analysis chamber, and the gas partial pressure mass spectrometer reads the standard gas pressure P2;

[0017] Step A6: The leakage rate of the positive pressure leak is calculated by comparing the accumulated gas pressure P1 after the positive pressure leak with the standard gas pressure P2.

[0018] The calibration of a partial pressure mass spectrometer includes the following steps:

[0019] Step B1: Close the first vacuum valve and use the pumping system to evacuate the pipeline;

[0020] Step B2: The gas supply system fills the pipeline with gas at an inlet pressure of P3; the gas passes through the sample preparation chamber, gas expansion chamber, and flow limiting component into the mass spectrometry analysis chamber; the flow limiting component can be configured to work alone or in conjunction with the sample inlet capillary.

[0021] Step B3: Use a magnetic levitation rotor vacuum gauge to obtain the pressure value P4 in the mass spectrometry analysis chamber; let the volume ratio C1 be the volume ratio of the gas expansion chamber to the sample preparation chamber, and the volume ratio C2 be the volume ratio of the mass spectrometry analysis chamber to the gas expansion chamber. Multiply the inlet pressure P3 by the volume ratios C1 and C2 to obtain the partial pressure P5 in the mass spectrometry analysis chamber.

[0022] Step B4: Obtain the correction coefficient of the partial pressure mass spectrometer by comparing the partial pressure P5 with the pressure value P4.

[0023] Preferably, the method further includes, before step A1, using a vacuum system to evacuate both ends of the positive pressure leak hole.

[0024] Preferably, in step A3, the gas flows into the sample preparation chamber under the action of a pressure difference for gas accumulation, and the accumulated gas expands into the gas expansion chamber, specifically as follows:

[0025] Under the action of pressure difference, the gas flows into the sample preparation chamber for gas accumulation. Based on the pressure shown by the first capacitor thin film vacuum gauge, after determining that the gas pressure change in the sample preparation chamber has reached the set value, the second vacuum valve is opened, and the accumulated gas expands into the gas expansion chamber.

[0026] Preferably, the length of the sample inlet capillary is trimmed according to the gas pressure output from the gas expansion chamber and the gas pressure that the vacuum partial pressure mass spectrometer can withstand, so that the gas pressure is reduced to an order of magnitude that the vacuum partial pressure mass spectrometer can accept before entering the mass spectrometry analysis chamber.

[0027] Beneficial effects:

[0028] (1) The gas pipeline needs to be filled with gas at a maximum pressure of 8 atmospheres, therefore it needs to be fully sealed with metal. High-pressure gas flowing into the mass spectrometry analysis chamber will cause damage to the vacuum gauge and gas partial pressure mass spectrometer, and contamination of the inner wall of the gas mass spectrometry analysis chamber. Therefore, the gas needs to undergo at least 9 orders of magnitude attenuation before entering the gas mass spectrometry analysis chamber, and the gas pressure needs to be reduced from 10 5 The Pa level needs to be reduced to 10. -4 Since the gas composition cannot change, this invention uses measures such as gas expansion, flow-limiting orifices, and sample introduction capillaries to continuously attenuate the gas, ensuring that the partial pressure mass spectrometer operates in a normal environment and that the gas composition remains unchanged. This provides the necessary conditions for the calibration of vacuum partial pressure mass spectrometers and positive pressure leaks.

[0029] (2) Combining the magnetic levitation rotor vacuum gauge set on the vacuum partial pressure mass spectrometer with the calibration scheme provided by the present invention, it is possible to use the same set of equipment to calibrate the vacuum partial pressure mass spectrometer under vacuum conditions on the basis of calibrating the positive pressure leak, so as to meet the comprehensive calibration needs of gas composition analysis and positive pressure leak detection in the field of manned spaceflight.

[0030] (3) Compared with the flow-limiting orifice, the sample introduction capillary is easier to cut and replace. The length of the sample introduction capillary can be cut or replaced according to the output gas pressure of the gas expansion chamber and the gas pressure that the vacuum partial pressure mass spectrometer can withstand. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the partial pressure mass spectrometer and positive pressure leak integrated calibration device of the present invention.

[0032] Among them, 1-positive pressure leak, 2-first vacuum valve, 5-second vacuum valve, 8-third vacuum valve, 9-fourth vacuum valve, 15-fifth vacuum valve, 17-sixth vacuum valve, 18-seventh vacuum valve, 20-eighth vacuum valve, 3-sample preparation chamber, 4-first capacitive thin-film vacuum gauge, 6-second capacitive thin-film vacuum gauge, 7-gas expansion chamber, 10-sample inlet capillary, 11-flow limiting orifice, 12-mass spectrometry analysis chamber, 13-vacuum partial pressure mass spectrometer, 14-gas extraction system, 16-magnetic levitation rotor vacuum gauge, 19-gas supply system. Detailed Implementation

[0033] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0034] This invention provides a comprehensive calibration scheme for a vacuum partial pressure mass spectrometer and a positive pressure leak. The device incorporates an inlet capillary. When calibrating a positive pressure leak with a high leakage rate, if the vacuum partial pressure mass spectrometer malfunctions due to excessive pressure, the inlet capillary branch is opened, thereby reducing the gas pressure entering the mass spectrometry chamber to 10. -4 The Pa level ensures the normal operation of the vacuum partial pressure mass spectrometer. Furthermore, by combining the magnetically levitated rotor vacuum gauge installed on the vacuum partial pressure mass spectrometer, the comprehensive calibration scheme provided by this invention enables the calibration of the vacuum partial pressure mass spectrometer under vacuum conditions using the same equipment, based on the calibration of positive pressure leaks. This meets the comprehensive calibration requirements of positive pressure environments for gas composition analysis and positive pressure leak detection in the manned spaceflight field.

[0035] Figure 1 A schematic diagram of the vacuum partial pressure mass spectrometer and the positive pressure leak integrated calibration device of the present invention is shown. Figure 1As shown, the device is composed of a positive pressure leak 1, a first vacuum valve 2, a second vacuum valve 5, a third vacuum valve 8, a fourth vacuum valve 9, a fifth vacuum valve 15, a sixth vacuum valve 17, a seventh vacuum valve 18, an eighth vacuum valve 20, a sample preparation chamber 3, a first capacitive thin-film vacuum gauge 4, a second capacitive thin-film vacuum gauge 6, a gas expansion chamber 7, a sample inlet capillary tube 9, a flow limiting orifice 11, a mass spectrometry analysis chamber 12, a vacuum partial pressure mass spectrometer 13, a gas extraction system 14, a magnetic levitation rotor vacuum gauge 16, and a gas supply system 19.

[0036] The specific connection relationship is as follows:

[0037] The gas supply system 19 is connected to the inlet of the positive pressure leak 1 via the eighth vacuum valve 20. The outlet of the positive pressure leak 1 is connected to the inlet of the sample preparation chamber 3 via the first vacuum valve 2. The eighth vacuum valve 20 is further connected to the inlet of the sample preparation chamber 3 via the seventh vacuum valve 18. The outlet of the sample preparation chamber 3 is connected to the inlet of the gas expansion chamber 7 via the second vacuum valve 5. The gas in the sample preparation chamber 3 expands to the gas expansion chamber 7 by static expansion. The outlet of the gas expansion chamber 7 is connected to the third vacuum valve 8. The third vacuum valve 8 is directly connected to the flow-limiting orifice 11 on one hand, and connected to the flow-limiting orifice 11 via the fourth vacuum valve 9 and the sample inlet capillary 9 in series on the other hand. The other end of the flow-limiting orifice 11 is connected to the mass spectrometry analysis chamber 12. Depending on the leakage rate of the positive pressure leak 1, the gas pressure is reduced to an acceptable level for the vacuum partial pressure mass spectrometer 13 by using the flow-limiting orifice 11 alone or by using the flow-limiting orifice 11 together with the sample inlet capillary 9, before entering the mass spectrometry analysis chamber 12. The gas extraction system 14 is connected to the mass spectrometry analysis chamber 12 via the fifth vacuum valve 15. Sample preparation chamber 3 and gas expansion chamber 7 are each connected to a capacitive thin-film vacuum gauge; mass spectrometry analysis chamber 12 is connected to a vacuum partial pressure mass spectrometer 13 and a magnetic levitation rotor vacuum gauge 16.

[0038] The working principle of this integrated calibration device is as follows:

[0039] Due to the pressure difference between the inlet and outlet, gas flows unidirectionally through the positive pressure leak 1 and accumulates statically. The sample preparation chamber 3 is used to prepare the standard gas required for calibration of the positive pressure leak and the vacuum partial pressure mass spectrometer, or the gas accumulation during positive pressure leak calibration. The gas in the sample preparation chamber 3 expands statically to the gas expansion chamber 7, and after the pressure drops, it enters the mass spectrometry analysis chamber through a flow-limiting orifice. The first capacitive thin-film vacuum gauge 4 measures the gas pressure in the sample preparation chamber, and the second capacitive thin-film vacuum gauge 6 measures the gas pressure in the gas expansion chamber. Based on the measured gas pressure, it can be determined whether the pressure change in the sample preparation chamber / gas expansion chamber has reached the set value. If it has, the subsequent valve is opened. In practice, the second vacuum valve 5 can also be kept open, connecting the sample preparation chamber and the gas expansion chamber. When the pressure change in the gas expansion chamber reaches the set value, the third vacuum valve 8 is opened, allowing the gas to enter the mass spectrometry analysis chamber 12 through the flow-limiting component. Mass spectrometry analysis chamber 12 provides a measurement environment for partial pressure measurement during vacuum partial pressure mass spectrometer calibration and for partial pressure measurement of leaking gas in positive pressure orifice. Flow limiting elements are installed inside the mass spectrometry analysis chamber to meet dynamic measurement conditions.

[0040] The flow-limiting component in this invention includes an inlet capillary 10 and a flow-limiting orifice 11. The flow-limiting orifice 11 can operate alone or in conjunction with the inlet capillary 9, depending on the leakage rate of the positive pressure leak 1. This switching between these two modes restricts the flow of gas in the gas expansion chamber 10, reducing its pressure to an acceptable level for the vacuum partial pressure mass spectrometer 13 before it enters the mass spectrometry analysis chamber 10. This ensures a normal operating environment for the partial pressure mass spectrometer 13 and maintains consistent gas composition, providing the necessary conditions for calibration of the vacuum partial pressure mass spectrometer 11 and the positive pressure leak 1.

[0041] The magnetic levitation rotor vacuum gauge 16 is used to measure the vacuum level in the mass spectrometry analysis chamber 12; the vacuum partial pressure mass spectrometer 13 is used to measure the gas partial pressure value in the mass spectrometry analysis chamber; the gas supply system 19 provides the required pressure of gas to the integrated calibration device through the vacuum valve 20; the gas extraction system 14 is connected to the device pipeline through the vacuum valve 15, which can remove the gas in the system. The gas extraction system has a selective gas extraction function, which can improve the gas extraction capacity of the gas extraction system and reduce the background interference of the mass spectrometry analysis chamber.

[0042] In a preferred embodiment, the device further includes a sixth vacuum valve 17, one end of which is connected to the pipeline between the eighth vacuum valve 20 and the seventh vacuum valve 18, and the other end is connected to the evacuation system 14 via the fifth vacuum valve 15. Opening the sixth vacuum valve 17 allows for the initial evacuation of the positive pressure leak's inlet and outlet using the evacuation system during the calibration process. Because the leak rate of the positive pressure leak varies depending on the type of gas, evacuation ensures a uniform gas composition and high calibration accuracy.

[0043] The positive pressure leak calibration includes the following steps:

[0044] Step A0: The eighth vacuum valve is closed, and the evacuation system 14 is used to evacuate air from the inlet and outlet of the positive pressure leak hole.

[0045] Step A1: Helium at a first pressure is introduced into the positive pressure leak inlet through the gas supply system 19 via the eighth vacuum valve 20, and nitrogen at a second pressure is introduced into the positive pressure leak outlet through the eighth vacuum valve 20, the seventh vacuum valve 20, and the first vacuum valve 2. The first pressure is greater than the second pressure. Generally, the second pressure is about 1 atmosphere. The first pressure is determined based on the parameters of the positive pressure leak inlet and outlet and the operating environment. In one embodiment, the first pressure is 2 atmospheres.

[0046] Step A2: Under the action of pressure difference, the gas flows into the sample preparation chamber 3 for gas accumulation. The accumulated gas expands to the gas expansion chamber 7. According to the pressure shown by the second capacitor thin film vacuum gauge 6, after determining that the gas pressure change has reached the set value, the third vacuum valve 8 is opened, and the gas enters the mass spectrometry analysis chamber 12 through the flow limiting orifice 11.

[0047] Here, the sample preparation chamber 3 and the gas expansion chamber 7 can be connected as one unit, or they can be separated for pressure change judgment and outlet control. In the latter case, the gas first flows into the sample preparation chamber 3 under the action of the pressure difference to accumulate gas. According to the pressure shown by the first capacitive thin-film vacuum gauge 4, after determining that the gas pressure change in the sample preparation chamber 3 has reached the set value, the second vacuum valve 5 is opened, and the accumulated gas expands to the gas expansion chamber 7. Then, according to the pressure shown by the second capacitive thin-film vacuum gauge 6, after determining that the gas pressure change has reached the set value, the third vacuum valve 8 is opened, and the gas enters the mass spectrometry analysis chamber 12 through the flow-limiting orifice 11.

[0048] Step A3: Determine if the gas partial pressure mass spectrometer 13 is open normally; if not, open the fourth vacuum valve 9 and use the sample inlet capillary 10 to restrict the flow of the accumulated gas again, then proceed to step A4; if it is open normally, proceed directly to step A4. The advantage of using the sample inlet capillary 10 is that, compared with the flow-limiting orifice, the sample inlet capillary 10 is easier to cut and replace. The length of the sample inlet capillary 10 can be cut or replaced according to the gas pressure output from the gas expansion chamber and the gas pressure that the vacuum partial pressure mass spectrometer 13 can withstand, so that the gas pressure is reduced to an acceptable level for the vacuum partial pressure mass spectrometer 13 before entering the mass spectrometry analysis chamber.

[0049] Step A4: Read the gas pressure P1 accumulated after positive pressure leak using gas partial pressure mass spectrometer 13;

[0050] Step A5: Close the first vacuum valve 2, and the gas supply system introduces standard gas into the sample preparation chamber 3; the standard gas enters the mass spectrometry analysis chamber 12 through the pipeline between the sample preparation chamber 3 and the mass spectrometry analysis chamber 12, and the gas partial pressure mass spectrometer 13 reads the standard gas pressure P2.

[0051] Step A6: The leakage rate of the positive pressure leak is calculated by comparing the accumulated gas pressure P1 after the positive pressure leak with the standard gas pressure P2.

[0052] Calibrating a partial pressure mass spectrometer includes the following steps:

[0053] Step B1: Close the first vacuum valve 2 and use the pumping system 14 to evacuate the pipeline.

[0054] Step B2: The gas supply system 19 pressurizes the pipeline with an inlet pressure of P3; the pressurized gas enters the mass spectrometry analysis chamber 12 through the sample preparation chamber, the gas expansion chamber, and the flow limiting component; the flow limiting component can be either the flow limiting orifice 11 working alone or the flow limiting orifice 11 working together with the sample inlet capillary 9.

[0055] Step B3: Use a magnetic levitation rotor vacuum gauge 16 to obtain the pressure value P4 of the mass spectrometry analysis chamber 12; let the volume ratio C1 be the volume ratio of the gas expansion chamber 7 to the sample preparation chamber 3, and the volume ratio C2 be the volume ratio of the mass spectrometry analysis chamber 12 to the gas expansion chamber 7. Multiply the inlet pressure P3 by the volume ratios C1 and C2 to obtain the partial pressure P5 in the mass spectrometry analysis chamber 12.

[0056] Step B4: Obtain the correction coefficient of the partial pressure mass spectrometer by comparing the partial pressure P5 with the pressure value P4.

[0057] The gas pipeline needs to be filled to a maximum pressure of 8 atmospheres, therefore requiring an all-metal seal. High-pressure gas flowing into the mass spectrometry analysis chamber would damage the vacuum gauge and gas partial pressure mass spectrometer, and contaminate the chamber walls. Therefore, the gas must undergo at least nine orders of magnitude attenuation before entering the chamber, and the gas pressure must be reduced from 10... 5 The Pa level needs to be reduced to 10. -4 The gas concentration is on the order of Pa, and the gas composition cannot be changed. Therefore, continuous gas attenuation is achieved through measures such as gas expansion, flow-limiting orifices, and sample introduction capillaries to meet the conditions for dynamic flow method calibration of gas partial pressure mass spectrometer and positive pressure leak.

[0058] This invention is of great significance for the comprehensive calibration requirements of gas composition analysis and positive pressure leak detection in the field of manned spaceflight.

[0059] The specific embodiments described above only illustrate the design principles of the present invention. The shapes and names of the components in this description may differ and are not limited. Therefore, those skilled in the art can modify or make equivalent substitutions to the technical solutions described in the foregoing embodiments; and these modifications and substitutions do not depart from the inventive spirit and technical solutions of the present invention, and should all fall within the protection scope of the present invention.

Claims

1. A comprehensive calibration device for partial pressure mass spectrometer and positive pressure leak, characterized in that, include: Gas supply system (19), positive pressure leak to be measured (1), sample preparation chamber (3), gas expansion chamber (7), sample inlet capillary (10), flow limiting orifice (11), mass spectrometry analysis chamber (12), vacuum partial pressure mass spectrometer (13), gas extraction system (14); The gas supply system (19) is connected to the inlet of the positive pressure leak (1) through the eighth vacuum valve (20). The outlet of the positive pressure leak (1) is connected to the inlet of the sample preparation chamber (3) through the first vacuum valve (2). The eighth vacuum valve (20) is further connected to the inlet of the sample preparation chamber (3) through the seventh vacuum valve (18). The sample preparation chamber (3) is used to prepare the standard gas required for the calibration of the positive pressure leak and the vacuum partial pressure mass spectrometer, as well as the gas accumulation during the calibration of the positive pressure leak. The outlet of the sample preparation chamber (3) is connected to the inlet of the gas expansion chamber (7) through the second vacuum valve (5). The gas in the sample preparation chamber (3) expands to the gas expansion chamber (7) by static expansion. The outlet of the gas expansion chamber (7) is connected to... Connect to the third vacuum valve (8). The third vacuum valve (8) is directly connected to the flow-limiting orifice (11) on one hand, and connected to the flow-limiting orifice (11) through the fourth vacuum valve (9) and the sample injection capillary (9) in series on the other hand. The other end of the flow-limiting orifice (11) is connected to the mass spectrometry analysis chamber (12). According to the leakage rate of the positive pressure leak (1), the gas pressure is reduced to the level that the vacuum partial pressure mass spectrometer (13) can accept by either the flow-limiting orifice (11) working alone or the flow-limiting orifice (11) working together with the sample injection capillary (9) before entering the mass spectrometry analysis chamber (12). The gas extraction system (14) is connected to the mass spectrometry analysis chamber (12) through the fifth vacuum valve (15). The sample preparation chamber (3) and the gas expansion chamber (7) are respectively connected to the capacitive thin-film vacuum gauge (4,6) for measuring the gas pressure inside the chamber; the mass spectrometry analysis chamber (12) is connected to the vacuum partial pressure mass spectrometer (13) and the magnetic levitation rotor vacuum gauge (16) for measuring the gas partial pressure and vacuum degree in the mass spectrometry analysis chamber (12) respectively.

2. The apparatus as claimed in claim 1, characterized in that, The device further includes a sixth vacuum valve (17), one end of which is connected to the pipeline between the eighth vacuum valve (20) and the seventh vacuum valve (18), and the other end is connected to the pumping system (14) through the fifth vacuum valve (15).

3. A method for integrated calibration of a partial pressure mass spectrometer and a positive pressure leak, characterized in that, Using the apparatus as described in claim 1 or 2, the method comprises: Positive pressure leak calibration includes the following steps: Step A1: Using the gas supply system (19), helium gas at the first pressure is introduced into the positive pressure leak inlet through the eighth vacuum valve (20), and nitrogen gas at the second pressure is introduced into the positive pressure leak outlet through the eighth vacuum valve (20), the seventh vacuum valve (20) and the first vacuum valve (2). The first pressure is greater than the second pressure. Step A2: Gas flows into the sample preparation chamber (3) under the action of pressure difference to accumulate gas. The accumulated gas expands to the gas expansion chamber (7). According to the pressure shown by the second capacitor thin film vacuum gauge (6), after the gas pressure change reaches the set value, the third vacuum valve (8) is opened and the gas enters the mass spectrometry analysis chamber (12) through the flow limiting orifice (11). Step A3: Determine whether the gas partial pressure mass spectrometer (13) is open normally; if it is not open, open the fourth vacuum valve (9) and use the sample introduction capillary (10) to restrict the flow of the accumulated gas again, and proceed to step A4; if it is open normally, proceed directly to step A4. Step A4: Read the gas pressure P1 accumulated after positive pressure leak using a gas partial pressure mass spectrometer (13); Step A5: Close the first vacuum valve (2), and the gas supply system introduces standard gas into the sample preparation chamber (3); the standard gas enters the mass spectrometry analysis chamber (12) through the pipeline between the sample preparation chamber (3) and the mass spectrometry analysis chamber (12), and the gas partial pressure mass spectrometer (13) reads the standard gas pressure P2; Step A6: The leakage rate of the positive pressure leak is calculated by comparing the accumulated gas pressure P1 after the positive pressure leak with the standard gas pressure P2. The calibration of a partial pressure mass spectrometer includes the following steps: Step B1: Close the first vacuum valve (2) and use the pumping system (14) to evacuate the pipeline; Step B2: The gas supply system (19) fills the pipeline with gas at an inlet pressure of P3; the gas enters the mass spectrometry analysis chamber (12) through the sample preparation chamber, gas expansion chamber, and flow limiting component; the flow limiting component is either a flow limiting orifice (11) working alone or a flow limiting orifice (11) working together with the sample inlet capillary (9); Step B3: Use a magnetic levitation rotor vacuum gauge (16) to obtain the pressure value P4 of the mass spectrometry analysis chamber (12); let the volume ratio C1 be the volume ratio of the gas expansion chamber (7) and the sample preparation chamber (3), and the volume ratio C2 be the volume ratio of the mass spectrometry analysis chamber (12) and the gas expansion chamber (7). Multiply the inlet pressure P3 by the volume ratios C1 and C2 to obtain the partial pressure P5 in the mass spectrometry analysis chamber (12); Step B4: Obtain the correction coefficient of the partial pressure mass spectrometer by comparing the partial pressure P5 with the pressure value P4.

4. The method as described in claim 3, characterized in that, The method further includes, prior to step A1, using a vacuum system (14) to evacuate both ends of the positive pressure leak hole.

5. The method as described in claim 3, characterized in that, In step A3, the gas flows into the sample preparation chamber (3) under the action of pressure difference to accumulate gas, and the accumulated gas expands into the gas expansion chamber (7) specifically as follows: Under the action of pressure difference, the gas flows into the sample preparation chamber (3) for gas accumulation. According to the pressure shown by the first capacitor thin film vacuum gauge (4), after the gas pressure change in the sample preparation chamber (3) reaches the set value, the second vacuum valve (5) is opened, and the accumulated gas expands to the gas expansion chamber (7).

6. The method as described in claim 3, characterized in that, Based on the gas pressure output from the gas expansion chamber and the gas pressure that the vacuum partial pressure mass spectrometer (13) can withstand, the length of the sample inlet capillary (10) is cut so that the gas pressure is reduced to an order of magnitude that the vacuum partial pressure mass spectrometer (13) can accept before entering the mass spectrometry analysis chamber (12).

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