A vacuum apparatus and method for sorbent pump performance testing

Abstract

The present application provides a kind of vacuum device and method for adsorbent pump performance test, comprising: vacuum pumping system, vacuum gas supply system, vacuum measurement system, auxiliary heating system.The main vacuum chamber air extractor set in vacuum pumping system is made of turbine molecular pump and front stage pump;Vacuum gas supply system is connected by small gas storage tank and standard gas cylinder with main vacuum chamber through vacuum pipeline, for gas supply in experimental process;Vacuum measurement system is made of each type gauge and residual gas analyzer, can measure the gas pressure of vacuum chamber and gas storage tank, analyzes and detects the residual gas composition and state of main vacuum chamber, measures the inflation rate in real time;Auxiliary heating system is made of power supply and its control system, maintains the temperature required for adsorbent pump to work, heats crucible to carry out coating treatment and wall treatment in initial stage.The vacuum air extractor set can be quickly pumped to 10 ‑6 Pa order of magnitude for adsorbent pump pumping speed performance research, and the influence of coating treatment on adsorbent pump performance is studied.

Description

Technical Field

[0001] This invention belongs to the field of vacuum measurement technology, specifically relating to a vacuum device and method for testing the performance of adsorbent pumps. Background Technology

[0002] Non-evaporative adsorbent pumps (NEGs), developed in the 1970s, are vacuum pumps made using the getter properties of transition metal materials. They are used for obtaining ultra-high / ultra-high vacuum environments and purifying gases. These pumps offer high pumping speeds and adsorption capacities for hydrogen and its isotopes, and feature simple structures, flexible installation, and are powered by an electrical supply to maintain their operating temperature. They are also easy to maintain and have seen widespread application in the fusion field. Forty-two modules based on ZAO alloy materials are installed in the divertor region of LHD in Japan, and TCV in Switzerland also uses this pump to test particle discharge.

[0003] However, adsorbent pumps can operate at room temperature and have pumping speeds for C, N, O, etc. The quality of the vacuum affects their pumping speed, making it difficult to effectively calibrate their pumping speed and performance in practical use, hindering standardization. Furthermore, there is a lack of research on the performance of adsorbent pumps after coating treatment. Therefore, there is an urgent need for a vacuum device for testing the performance of adsorbent pumps, capable of quantitatively calibrating their pumping speed, and effectively solving the above problems. Summary of the Invention

[0004] To address the aforementioned shortcomings of existing technologies, this invention provides a vacuum device and method for testing the performance of adsorbent pumps. The vacuum pump unit can rapidly evacuate to a vacuum level of 10... -6 With pressure sensors and inflation valves operating at the Pa level, the differential pressure sensor and inflation valve can accurately calculate the inflation volume, which can be used to study the pumping speed performance of adsorbent pumps. At the same time, it can also be used to study the effect of coating treatment on the performance of adsorbent pumps.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] Vacuum pumping system, vacuum supply system, vacuum measurement system, auxiliary heating system

[0007] The main vacuum chamber pumping unit in the vacuum pumping system consists of a turbomolecular pump and a backing pump; the vacuum gas supply system consists of a small gas storage tank and a standard gas storage bottle connected to the main vacuum chamber through vacuum pipelines, used to supply gas during the experiment and measure changes in pumping speed; the vacuum measurement system consists of various types of gauges and a residual gas analyzer, which can measure the gas pressure in the vacuum chamber and the gas storage tank, analyze and detect the composition and state of residual gas in the main vacuum chamber, and measure the charging rate in real time; the auxiliary heating system consists of a power supply and its control system, used to maintain the temperature required for the adsorbent pump to operate, and to heat the crucible for coating treatment and initial stage wall treatment.

[0008] Its characteristic is that, using the vacuum device of this application, the vacuum pumping unit can quickly evacuate to a vacuum level of 10. -6 The pressure differential sensor, operating on the Pa scale, can accurately calculate the inflation rate and can be used to study the pumping speed performance of adsorbent pumps. It can also be used to study the effect of coating treatment on the performance of adsorbent pumps.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] A vacuum device for testing the performance of an adsorbent pump includes a vacuum pumping system, a vacuum supply system, a vacuum measurement system, and an auxiliary heating system.

[0011] The vacuum pumping system consists of a turbomolecular pump and a backing pump (typically a rotary vane pump, vortex pump, etc.), connected to the main vacuum chamber via a gate valve, and an exhaust pump connected to a second small gas storage tank via a vacuum pipeline. The vacuum gas supply system consists of a first and second small gas storage tank and a standard gas storage bottle connected to the main vacuum chamber via a vacuum pipeline, used for gas supply during the experiment. The vacuum measurement system consists of a first gauge tube, a second gauge tube, a residual gas analyzer, a first differential pressure sensor, and a second differential pressure sensor, capable of measuring the gas pressure in the main vacuum chamber and the gas storage tank, analyzing and detecting the composition and state of residual gas in the main vacuum chamber, and measuring the charging rate in real time. The auxiliary heating system consists of a power supply and its control system, namely, a power supply for the adsorbent pump, a power supply for the crucible, a power supply for the wall vacuum chamber baking, and its control system, used to maintain the temperature required for the adsorbent pump to operate, and to heat the crucible for coating treatment and initial wall treatment.

[0012] Furthermore, the pumping unit, consisting of a turbomolecular pump and a backing pump, can rapidly pump the vacuum level in the system to 10. -6 The order of magnitude is Pa.

[0013] Furthermore, the residual gas analyzer monitors the gas composition and partial pressure of the main vacuum chamber in real time to understand the real-time vacuum status of the vacuum chamber.

[0014] Furthermore, the first and second differential pressure sensors accurately measure the pressure difference between the first and second gas storage tanks through vacuum pipes and manual valves.

[0015] Furthermore, the first and second valves are controlled by the host computer via a serial communication protocol to replenish gas to the first and second small gas storage tanks during the experiment.

[0016] Furthermore, the venting pump is connected to a second small gas storage tank via a vacuum pipeline. It is used to vent the gas storage tank when it is contaminated, so as to ensure the purity of the working gas during the experiment. It is also used to replace the gas to provide a variety of working gases.

[0017] Furthermore, the gas filling valve is controlled by the host computer control software to fill the main vacuum chamber with a calibration gas (usually hydrogen or deuterium) at a preset value, and the data is recorded in the host computer.

[0018] Furthermore, the power supply for the adsorbent pump meets the current range required for the adsorbent pump to transition from its optimal operating state to its regeneration state; the power supply for baking the vacuum chamber wall is used to bake the vacuum chamber wall to release gas; and the power supply for the crucible is used to coat the adsorbent pump inside the vacuum chamber with materials such as lithium or boron.

[0019] Furthermore, a temperature measuring component is attached to the adsorbent pump and the crucible to measure the temperature of the adsorbent pump and the crucible in real time.

[0020] This invention provides a testing method for a vacuum device used for testing the performance of adsorbent pumps, comprising the following steps:

[0021] Step 1: Start the backing pump and turbomolecular pump, open the gate valve, and maintain the vacuum level in the main vacuum chamber at 10. -6 Pa level;

[0022] Step 2: Turn on the residual gas analyzer to monitor the gas composition in the main vacuum chamber;

[0023] Step 3: Turn on the power control system to supply power to the adsorbent pump, raise its temperature to the set temperature and maintain it (usually within the range of room temperature to 200 degrees Celsius, depending on the calibration requirements), and then close the gate valve above the turbomolecular pump.

[0024] Step 4: Control the opening of the inflation valve to fill the main vacuum chamber with working gas and maintain it at a certain pressure for a certain period of time. Calculate the inflation rate and the amount of gas injected based on the changes in the first gauge tube above the second differential pressure sensor and the second gas storage tank. This completes the pumping speed calibration of the adsorbent pump at this pressure.

[0025] Step 5: Use the first valve to replenish the first small gas storage tank and the second valve to replenish the second small gas storage tank in a timely manner to ensure sufficient gas volume. Repeat step 4 multiple times to calibrate the pumping speed under different gas pressures.

[0026] Step 6: After the experiment, open the slide valve to maintain the vacuum.

[0027] This invention also provides another testing method for a vacuum device used for testing the performance of adsorbent pumps, including a pumping speed calibration experiment after coating treatment, comprising the following steps:

[0028] Step 1: Place the crucible containing materials such as lithium or boron into the main vacuum chamber, start the back pump and turbomolecular pump, open the gate valve, and maintain the vacuum level of the main vacuum chamber to the order of 10⁻⁶ Pa.

[0029] Step 2: Close the baffle valve and control the crucible power supply to heat the crucible. The coating material inside the crucible evaporates and adheres to the adsorbent pump, and the coating treatment is completed.

[0030] Step 3: Open the gate valve, turn off the crucible power, turn on the adsorbent pump power to raise the temperature to 200°C and maintain it, then close the gate valve above the turbomolecular pump.

[0031] Step 4: Control the opening of the inflation valve to fill the main vacuum chamber with working gas and maintain it at a certain pressure for a certain period of time. Calculate the filling amount based on the changes in the second differential pressure sensor and the second gauge tube above the second gas storage tank. This completes the pumping speed calibration of the adsorbent pump at this pressure after coating treatment.

[0032] Step 5: Use the first valve to replenish the first small gas storage tank and the second valve to replenish the second small gas storage tank in a timely manner to ensure sufficient gas volume. Repeat step 4 multiple times to calibrate the pumping speed under different gas pressures.

[0033] Step 6: After the experiment, open the slide gate valve to maintain the vacuum. The beneficial effects of this invention are:

[0034] 1. This invention can be used to assess the impact of different operating temperatures, different saturation capacities, and high gas pressures on the pumping speed performance of adsorbent pumps, thus improving performance testing standards.

[0035] 2. This invention can be used to study the effects of different surface coating treatments on the performance of adsorbent pumps;

[0036] 3. The present invention is equipped with an vent valve, which can vent and replace the gas in the small gas storage tank, and can use multiple gases as working gases without causing contamination between them. Attached Figure Description

[0037] To more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 This is a structural block diagram of the vacuum device for testing the performance of adsorbent pumps according to the present invention;

[0039] In the diagram: 1-Working gas tank, 2-First valve, 3-First differential pressure sensor, 4-First small gas storage tank, 5-Second differential pressure sensor, 6-Second valve, 7-First gauge tube, 8-Second small gas storage tank, 9-Manual valve, 10-Vacuum pump, 11-Inflation valve, 12-Residual gas analyzer, 13-Second gauge tube, 14-Crucible, 15-Gate valve, 16-Turbomolecular pump, 17-Backing pump. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0041] like Figure 1 As shown, the vacuum device for testing the performance of an adsorbent pump according to the present invention includes a vacuum pumping system, a vacuum supply system, a vacuum measurement system, and an auxiliary heating system; specifically, it includes a working gas tank 1, a first valve 2, a second valve 6, a first differential pressure sensor 3, a second differential pressure sensor 5, a first gauge tube 7, a second gauge tube 13, a first small gas storage tank 4, a second small gas storage tank 8, a manual valve 9, an evacuation pump 10, a charging valve 11, a residual gas analyzer 12, a crucible 14, a gate valve 15, a turbomolecular pump 16, and a backing pump 17.

[0042] The vacuum pumping system consists of a turbomolecular pump 16 and a forepump 17, connected to the main vacuum chamber via a gate valve 15, and an exhaust pump connected to the second small gas storage tank 8 via a vacuum pipeline. The vacuum gas supply system consists of a first small gas storage tank and a standard gas storage bottle connected to the main vacuum chamber via a vacuum pipeline, used for gas supply during the experiment. The vacuum measurement system consists of a first gauge tube, a second gauge tube, a residual gas analyzer, a first differential pressure sensor, and a second differential pressure sensor, capable of measuring the gas pressure in the main vacuum chamber and the gas storage tank, analyzing and detecting the composition and state of the residual gas in the main vacuum chamber, and measuring the inflation rate in real time. The auxiliary heating system consists of a power supply and its control system, namely, a power supply for the adsorbent pump, a power supply for the crucible, a power supply for the wall vacuum chamber baking, and its control system, used to maintain the temperature required for the adsorbent pump to operate, and to heat the crucible for coating treatment and initial wall treatment.

[0043] In this embodiment, the working gas tank 1 provides working gas to the device, and the first small gas storage tank 4 is replenished with gas through the first valve 2. The first small gas storage tank 4 is replenished with gas through the second valve 6. The second small gas storage tank 8 is connected to the venting pump 10 through the manual valve 9, which is used to replace the gas in the tank when the gas is contaminated or when the working gas is changed. At the same time, it is connected to the main vacuum chamber through the inflation valve 11 for supplying gas during the experiment.

[0044] In this embodiment, the vacuum pumping system of the main vacuum chamber consists of a turbomolecular pump 16 and a pre-stage pump 17, which can pump the main vacuum to 10. -6 The real-time gas pressure data of the main vacuum chamber is obtained by the second gauge tube 13, which is in the Pa range; the gas composition and partial pressure in the main vacuum chamber are monitored in real time by the residual gas analyzer 12.

[0045] In this embodiment, the gas filling valve 11 controls the valve opening to fill the main vacuum chamber with working gas at a preset value. When the adsorbent pump is working, the gas pressure can be maintained at a certain value. By changing the preset value, the pumping speed of the adsorbent pump under different gas pressures can be calibrated through calculation.

[0046] In this embodiment, the first differential pressure sensor 3 connects the working gas tank 1 and the first small gas storage tank 4 through a vacuum pipe to monitor the differential pressure data in real time during the experiment. The second differential pressure sensor 5 connects the first small gas storage tank 4 and the second small gas storage tank 8 through a vacuum pipe to record the differential pressure data during the experiment in order to calculate the amount of working gas charged.

[0047] In this embodiment, the residual gas analyzer 12 and the second gauge tube 13 are connected to the main vacuum chamber through a vacuum pipe. The crucible 14 is suspended inside the main vacuum chamber. The gate valve 15 connects the main vacuum chamber to the pumping unit. The turbomolecular pump 16 and the forepump 17 are fixed to the main vacuum chamber wall through a bracket. NEG is a test adsorbent pump.

[0048] The testing method of the present invention includes the following steps:

[0049] Step 1: Start the forepump 17 and turbomolecular pump 16, open the gate valve 15, and maintain the vacuum level of the main vacuum chamber at 10. -6 Pa level;

[0050] Step 2: Turn on the residual gas analyzer 12 to monitor the gas composition in the main vacuum chamber;

[0051] Step 3: Turn on the power control system to supply power to the adsorbent pump, raise its temperature to the set temperature and maintain it (usually in the range of room temperature to 200 degrees Celsius, depending on the calibration requirements), and then close the gate valve 15 above the turbomolecular pump.

[0052] Step 4: Control the opening of the inflation valve 11 to fill the main vacuum chamber with working gas and maintain it at a certain pressure for a certain period of time. Calculate the filling amount based on the changes in the second differential pressure sensor 5 and the first gauge tube 7 above the second small gas storage tank 8. This will complete the pumping speed calibration of the adsorbent pump at this pressure.

[0053] Step 5: Use the first valve 2 and the second valve 6 to replenish the first small gas storage tank 4 and the second small gas storage tank 8 in a timely manner to ensure sufficient gas volume. Repeat step 4 multiple times to calibrate the pumping speed under different gas pressures.

[0054] Step 6: After the experiment, open the slide valve 15 and maintain the vacuum.

[0055] Further, a pumping speed calibration experiment was conducted after coating treatment, including the following steps:

[0056] Step 1: Place the crucible containing materials such as boron into the main vacuum chamber, start the back pump and turbomolecular pump, open the gate valve, and maintain the vacuum level of the main vacuum chamber to the order of 10⁻⁶ Pa.

[0057] Step 2: Close the baffle valve and control the crucible power supply to heat the crucible. The coating material inside the crucible evaporates and adheres to the adsorbent pump, and the coating treatment is completed.

[0058] Step 3: Open the gate valve, turn off the crucible power, turn on the adsorbent pump power to raise the temperature to 200°C and maintain it, then close the gate valve above the turbomolecular pump.

[0059] Step 4: Control the opening of the inflation valve to fill the main vacuum chamber with working gas and maintain it at a certain pressure for a certain period of time. Calculate the filling amount based on the changes in the second differential pressure sensor and the second gauge tube above the second gas storage tank. This completes the pumping speed calibration of the adsorbent pump at this pressure after coating treatment.

[0060] Step 5: Use the first valve to replenish the first small gas storage tank and the second valve to replenish the second small gas storage tank in a timely manner to ensure sufficient gas volume. Repeat step 4 multiple times to calibrate the pumping speed under different gas pressures.

[0061] Step 6: After the experiment, open the slide valve to maintain the vacuum.

[0062] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A vacuum device for testing the performance of adsorbent pumps, characterized in that: It includes a vacuum pumping system, a vacuum supply system, a vacuum measurement system, and an auxiliary heating system; The vacuum pumping system consists of a turbomolecular pump and a backing pump, connected to the main vacuum chamber via a gate valve. The vacuum supply system supplies gas during the experiment; a first small gas storage tank, a second small gas storage tank, and a standard gas storage cylinder are connected to the main vacuum chamber via vacuum pipes. The vacuum measurement system consists of a first gauge tube above the second small gas storage tank, a second gauge tube, a residual gas analyzer, a first differential pressure sensor, and a second differential pressure sensor. The first differential pressure sensor connects the standard gas storage cylinder to the first small gas storage tank via a vacuum pipe, and the second differential pressure sensor connects to the standard gas storage cylinder via a vacuum pipe. The first small gas storage tank is connected to the second small gas storage tank. The second small gas storage tank is connected to the main vacuum chamber through a gas filling valve. The residual gas analyzer and the second gauge tube are connected to the main vacuum chamber through a vacuum pipeline. The vacuum measurement system is used to analyze and detect the composition and state of the residual gas in the main vacuum chamber and to measure the gas filling rate in real time. The auxiliary heating system consists of a power supply and a power control system, namely, a power supply for the adsorbent pump, a power supply for the crucible, a power supply for the wall vacuum chamber baking, and a corresponding power control system. It is used to maintain the temperature required for the adsorbent pump to work, heat the crucible for coating treatment, and perform wall treatment in the initial stage. The venting pump is connected to the second small gas storage tank through a vacuum pipeline. It is used to vent the gas in the tank when it is contaminated, so as to ensure the purity of the working gas during the experiment. It is also used to replace the gas to provide a variety of working gases. The power supply for the adsorbent pump meets the voltage and current range required for the adsorbent pump to transition from its optimal operating state to its regeneration state; the power supply for baking the wall vacuum chamber is an AC or DC power supply with adjustable output voltage, used for baking the vacuum chamber wall to release gas; the power supply for the crucible is used to treat the adsorbent pump in the main vacuum chamber with lithium or boron coating material.

2. The vacuum device for testing the performance of an adsorbent pump according to claim 1, characterized in that: The pumping unit, consisting of a turbomolecular pump and a backing pump, can rapidly pump the vacuum level in the system to 10. -6 The order of magnitude is Pa.

3. The vacuum device for testing the performance of an adsorbent pump according to claim 1, characterized in that: The residual gas analyzer monitors the gas composition and partial pressure of the main vacuum chamber in real time to understand the real-time vacuum status of the chamber.

4. The vacuum device for testing the performance of an adsorbent pump according to claim 1, characterized in that: The first differential pressure sensor and the second differential pressure sensor accurately measure the pressure difference between the first small gas storage tank and the second small gas storage tank through a vacuum pipeline and a manual valve.

5. A vacuum device for testing the performance of an adsorbent pump according to claim 1, characterized in that: It includes a first valve and a second valve. The standard gas cylinder is connected to the first small gas tank through the first valve, and the first small gas tank is connected to the second small gas tank through the second valve. During the experiment, the first valve and the second valve are used to replenish the first small gas tank and the second small gas tank.

6. A vacuum device for testing the performance of an adsorbent pump according to claim 1, characterized in that: The inflation valve is controlled by the host computer control software to control the valve opening, and to fill the main vacuum chamber with calibration gas at a preset value, and record the data in the host computer.

7. A vacuum device for testing the performance of an adsorbent pump according to claim 1, characterized in that: The temperature measuring component is attached to the adsorbent pump and the crucible to measure the temperature of the adsorbent pump and the crucible in real time. The temperature measuring component is a type K thermocouple.

8. A test method for a vacuum device for testing the performance of an adsorbent pump according to any one of claims 1-7, characterized in that, Includes the following steps: Step 1: Start the backing pump and turbomolecular pump, open the gate valve, and maintain the vacuum level in the main vacuum chamber at 10. -6 Pa level; Step 2: Turn on the residual gas analyzer to monitor the gas composition in the main vacuum chamber; Step 3: Turn on the power control system to supply power to the adsorbent pump, raise its temperature to the set temperature and maintain it within the range of room temperature to 200 degrees Celsius, then close the gate valve above the turbomolecular pump. Step 4: Control the opening of the inflation valve to fill the main vacuum chamber with working gas and maintain it at a certain pressure for a certain period of time. Calculate the inflation rate and the amount of gas injected based on the changes in the first gauge tube above the second small gas storage tank, which is the pumping speed calibration of the adsorbent pump at this pressure. Step 5: Use the first valve to replenish the first small gas storage tank and the second valve to replenish the second small gas storage tank in a timely manner to ensure sufficient gas volume. Repeat step 4 multiple times to calibrate the pumping speed under different gas pressures. Step 6: After the experiment, open the slide valve to maintain the vacuum.

9. A test method for a vacuum device for testing the performance of an adsorbent pump according to any one of claims 1-7, characterized in that, The pumping speed calibration experiment after coating treatment includes the following steps: Step 1: Place the crucible containing lithium or boron into the main vacuum chamber, start the backing pump and turbomolecular pump, open the gate valve, and maintain the vacuum level of the main vacuum chamber at 10. -6 Pa level; Step 2: Close the baffle valve and control the crucible power supply to heat the crucible. The coating material inside the crucible evaporates and adheres to the adsorbent pump, and the coating treatment is completed. Step 3: Open the gate valve, turn off the crucible power, turn on the adsorbent pump power to raise the temperature to 200°C and maintain it, then close the gate valve above the turbomolecular pump. Step 4: Control the opening of the inflation valve to fill the main vacuum chamber with working gas and maintain it at a certain pressure for a certain period of time. Calculate the filling amount based on the changes in the first gauge tube above the second differential pressure sensor and the second small gas storage tank. This completes the pumping speed calibration of the adsorbent pump at this pressure after coating treatment. Step 5: Use the first valve to replenish the first small gas storage tank and the second valve to replenish the second small gas storage tank in a timely manner to ensure sufficient gas volume. Repeat step 4 multiple times to calibrate the pumping speed under different gas pressures. Step 6: After the experiment, open the slide valve to maintain the vacuum.

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