A vacuum helium leak detection tool and method suitable for nuclear fusion reaction device

Abstract

The present invention belongs to the technical field of nuclear fusion vacuum leak detection, and specifically relates to a vacuum helium leak detection tool and method suitable for a nuclear fusion reaction device, the vacuum helium leak detection tool comprising a main exhaust system, a front exhaust system, a helium mass spectrometer leak detector, a main exhaust branch, a rough vacuum exhaust branch and a front exhaust branch; the main exhaust system comprises a plurality of main exhaust branches, the front exhaust system comprises a rough vacuum exhaust branch and a plurality of front exhaust branches, and the helium mass spectrometer leak detector is connected to the front exhaust branch. The present invention can quickly find out tiny leaks appearing on the vacuum chamber of a fusion reaction device, prevent tiny leaks from affecting the normal plasma discharge experiment of the fusion device, causing the fusion device to stop running, and causing physical damage to the vacuum equipment and diagnostic equipment around the fusion device.

Description

Technical Field

[0001] The invention belongs to the technical field of nuclear fusion vacuum leak detection, and in particular relates to a vacuum helium leak detection tool and method suitable for a nuclear fusion reaction device. Background Art

[0002] In order to ensure long-term safe operation of future fusion reactors, the first thing to do is to ensure that the chamber that generates and maintains the plasma is a closed ultra-high vacuum environment with a vacuum degree of 10 -5 Pa level. However, in the manufacturing of the vacuum chamber of the fusion device, the installation of the window equipment, and the device experiment process, due to the defects of the vacuum chamber shell material, the installation deviation of the window equipment, the influence of electromagnetic force or plasma rupture during the experiment, tiny leaks will appear in the vacuum chamber body and the connecting components, which will directly affect the normal plasma discharge experiment of the fusion device and cause the fusion device to stop operating. If the leak point continues to increase, it will cause physical damage to the vacuum equipment and diagnostic equipment around the fusion device. Therefore, the development and application of effective vacuum leak detection systems and leak detection methods is one of the current focuses of tokamak plasma engineering research, and it is also one of the engineering foundations and problems that must be solved for the engineering design, safe operation, and safety protection of the next generation of large-scale magnetic confinement devices.

[0003] Therefore, it is necessary to provide a vacuum helium leak detection tool and method suitable for a nuclear fusion reaction device to solve the deficiencies in the prior art. Summary of the invention

[0004] The purpose of the present invention is to provide a vacuum helium leak detection tool and method suitable for a nuclear fusion reaction device in view of the above-mentioned deficiencies in the prior art, so as to quickly find out tiny leaks appearing on the vacuum chamber of the fusion reaction device to prevent physical damage to the vacuum equipment and diagnostic equipment around the fusion device.

[0005] The technical solution of the present invention is:

[0006] A vacuum helium leak detection tool suitable for a nuclear fusion reaction device, the vacuum helium leak detection tool comprising a main exhaust system, a front exhaust system, a helium mass spectrometer leak detector, a main exhaust branch, a rough vacuum exhaust branch and a front exhaust branch;

[0007] The main air extraction system includes several main air extraction branches, each of which is connected in parallel. The main air extraction branches include an ultra-high vacuum pneumatic gate valve V1-1, a turbomolecular pump P1-1, and a high vacuum pneumatic baffle valve V4-1. The front end of the ultra-high vacuum pneumatic gate valve V1-1 is connected to the vacuum chamber, and the rear end of the ultra-high vacuum pneumatic gate valve V1-1 is connected to the turbomolecular pump P1-1 and the high vacuum pneumatic baffle valve V4-1 in sequence.

[0008] The front-stage exhaust system includes a rough vacuum exhaust branch and a plurality of front-stage exhaust branches, each of which is connected in parallel, and the rough vacuum exhaust branch and the front-stage exhaust branch are connected in parallel, the front end of the ultra-high vacuum pneumatic gate valve V2-1 of the front-stage exhaust branch is connected to the rear end of the high vacuum pneumatic damper valve V4-1 of the main exhaust branch, and the ultra-high vacuum pneumatic gate valves V3-1 and V3-2 of the rough vacuum exhaust branch are connected to the rear end of the high vacuum pneumatic damper valve V4-1 of the main exhaust branch;

[0009] The helium mass spectrometer leak detector is connected to the front-stage exhaust branch.

[0010] The front ends of the two ultra-high vacuum pneumatic gate valves V3-1 and V3-2 in the rough vacuum exhaust branch are respectively connected to the rear end of the high vacuum pneumatic baffle valve V4-1, and the rear ends of the ultra-high vacuum pneumatic gate valves V3-1 and V3-2 are respectively connected to the air inlets of two Roots vacuum pumps P4-1 and P4-2, and the air outlets of the Roots vacuum pumps P4-1 and P4-2 are respectively connected to the rotary vane pumps P5-1 and P5-2.

[0011] The front end of the ultra-high vacuum pneumatic gate valve V2-1 of the front-stage exhaust branch is connected to the rear end of the high vacuum pneumatic baffle valve V4-1 of the main exhaust branch, the rear end of the ultra-high vacuum pneumatic gate valve V2-1 is connected to the turbomolecular pump P3-1, the outlet of the molecular pump P3-1 is connected to the vacuum chamber C1-1, and the other end of the vacuum chamber C1-1 is connected to the air inlets of the direct-connected pumps P6-1 and P6-2 respectively through the high vacuum pneumatic baffle valves V6-5 and V6-6.

[0012] The helium mass spectrometer leak detector is connected to the vacuum chamber C1-1 through a high vacuum pneumatic baffle valve V6-1 to analyze the size of the leak point on the vacuum chamber.

[0013] The two Roots vacuum pumps P4-1, P4-2 and the two rotary vane pumps P5-1, P5-2 in the rough vacuum exhaust branch pump the main vacuum chamber from atmospheric pressure to below 10Pa, so that the turbomolecular pump P1-1 has the starting working conditions.

[0014] The turbomolecular pump P3-1 and the direct-connected pumps P6-1 and P6-2 in the front-stage exhaust branch exhaust the gas extracted by the turbomolecular pump P1-1 in the main exhaust branch into the atmosphere in stages.

[0015] The leak detection method of the vacuum helium leak detection tool suitable for a nuclear fusion reaction device comprises the following steps:

[0016] Step (1) Open the ultra-high vacuum pneumatic gate valve V1-1 and the ultra-high vacuum pneumatic gate valves V3-1 and V3-2, and start the rotary vane pumps P5-1 and P5-2 and the direct-connected pumps P6-1 and P6-2;

[0017] Step (2) When the vacuum degree of the vacuum chamber is less than 1000 Pa, start the Roots vacuum pumps P4-1 and P4-2;

[0018] Step (3) When the vacuum degree of the vacuum chamber is less than 10Pa, start the turbomolecular pump P1-1, and when the vacuum degree of the vacuum chamber C1-1 is less than 10Pa, start the turbomolecular pump P3-1, and when the main vacuum degree is less than 10-2Pa, open the ultra-high vacuum pneumatic gate valves V2-1 and V2-2, and close the Roots vacuum pumps P4-1 and P4-2 and the rotary vane pumps P5-1 and P5-2;

[0019] Step (4) starting the helium mass spectrometer leak detector 3, opening the high vacuum pneumatic damper valve V6-1 and calibrating the helium mass spectrometer leak detector 3;

[0020] Step (5) uses negative pressure blowing method to perform helium mass spectrometry leak detection on the vacuum chamber to find tiny leak points.

[0021] The present invention has the following beneficial effects:

[0022] The present invention can quickly find tiny leaks on the vacuum chamber of a fusion reaction device, prevent the tiny leaks from affecting the normal plasma discharge experiment of the fusion device, causing the fusion device to stop running, and physically damage vacuum equipment and diagnostic equipment around the fusion device. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic structural diagram of a vacuum helium leak detection tool for a nuclear fusion reaction device provided by the present invention;

[0024] Among them: 1-main exhaust system; 2-pre-exhaust system; 3-helium mass spectrometer leak detector; 4-main exhaust branch; 5-rough vacuum exhaust branch; 6-pre-exhaust branch; 7-vacuum chamber; P1-1, P1-2, P1-3, P1-4 are turbomolecular pumps for the main exhaust branch; P3-1, P3-2 are turbomolecular pumps for the pre-exhaust branch; P4-1, P4-2 are Roots vacuum pumps for the rough vacuum exhaust branch; P5-1, P5-2 are rotary vane pumps for the pre-exhaust branch; P6-1, P6-2, P6-3, P6-4 are direct-connected pumps for the pre-exhaust branch; V1-1, V1-2, V1-3, V1-4 are ultra-high vacuum pneumatic gate valves for the main exhaust branch; V2- 1. V2-2 is the ultra-high vacuum pneumatic gate valve of the front-stage exhaust branch; V3-1 and V3-2 are ultra-high vacuum pneumatic gate valves of the rough vacuum exhaust branch; V4-1, V4-2, V4-3 and V4-4 are high vacuum pneumatic baffle valves of the main exhaust branch; V6-1, V6-2, V6-3, V6-4, V6-5, V6-6, V6-7 and V6-8 are high vacuum pneumatic baffle valves of the front-stage exhaust branch; C1-1 and C1-2 are vacuum chambers of the front-stage exhaust branch; G1-1, G1-2, G1-3, G1-4, G1-5, G1-6, G1-7 and G1-8 are resistance gauges; G2-1, G2-2, G2-3 and G2-4 are ionization gauges. DETAILED DESCRIPTION

[0025] The present invention is further described below in conjunction with the embodiments and drawings:

[0026] The present invention provides a vacuum helium leak detection tool suitable for a nuclear fusion reaction device, the vacuum helium leak detection tool comprising a main exhaust system 1, a front exhaust system 2, a helium mass spectrometer leak detector 3, a main exhaust branch 4, a rough vacuum exhaust branch 5 and a front exhaust branch 6;

[0027] The main air extraction system 1 includes a plurality of main air extraction branches 4, each of which is connected in parallel. The main air extraction branch 4 includes an ultra-high vacuum pneumatic gate valve V1-1, a turbomolecular pump P1-1, and a high vacuum pneumatic baffle valve V4-1. The front end of the ultra-high vacuum pneumatic gate valve V1-1 is connected to the vacuum chamber 7, and the rear end of the ultra-high vacuum pneumatic gate valve V1-1 is connected to the turbomolecular pump P1-1 and the high vacuum pneumatic baffle valve V4-1 in sequence.

[0028] The front-stage exhaust system 2 includes a rough vacuum exhaust branch 5 and a plurality of front-stage exhaust branches 6, each of which is connected in parallel, and the rough vacuum exhaust branch 5 and the front-stage exhaust branch 6 are connected in parallel, the front end of the ultra-high vacuum pneumatic gate valve V2-1 of the front-stage exhaust branch 6 and the rear end of the high vacuum pneumatic baffle valve V4-1 of the main exhaust branch 4 are connected through a pipeline, and the ultra-high vacuum pneumatic gate valves V3-1 and V3-2 of the rough vacuum exhaust branch 5 and the rear end of the high vacuum pneumatic baffle valve V4-1 of the main exhaust branch 4 are connected through a pipeline;

[0029] The helium mass spectrometer leak detector 3 is connected to the front-stage exhaust branch 6 through a high vacuum pneumatic baffle valve V6-1.

[0030] The front end of the ultra-high vacuum pneumatic gate valve V1-1 in the main exhaust branch 4 is connected to the vacuum chamber 7 through an ultra-high vacuum metal sealing flange, and the rear end is connected to the air inlet of the turbomolecular pump P1-1 through an ultra-high vacuum fluororubber sealing flange. The air outlet of the turbomolecular pump P1-1 is connected to the front end of the high vacuum pneumatic baffle valve V4-1 through an ultra-high vacuum fluororubber sealing flange.

[0031] The front-stage exhaust system 2 includes a rough vacuum exhaust branch 5 and a plurality of front-stage exhaust branches 6. The front ends of the two ultra-high vacuum pneumatic gate valves V3-1 and V3-2 in the rough vacuum exhaust branch 5 are respectively connected to the rear end pipeline of the high vacuum pneumatic baffle valve V4-1 through ultra-high vacuum fluororubber sealing flanges, and the rear ends of the ultra-high vacuum pneumatic gate valves V3-1 and V3-2 are respectively connected to the air inlets of two Roots vacuum pumps P4-1 and P4-2 through high vacuum fluororubber sealing flanges. The air outlets of the Roots vacuum pumps P4-1 and P4-2 are connected to the rotary vane pumps P5-1 and P5-2 through high vacuum fluororubber sealing flanges.

[0032] The front end of the ultra-high vacuum pneumatic gate valve V2-1 of the front-stage exhaust branch 6 is connected to the pipeline at the rear end of the high vacuum pneumatic baffle valve V4-1 of the main exhaust branch 4 through an ultra-high vacuum fluororubber sealing flange, the rear end of the ultra-high vacuum pneumatic gate valve V2-1 is connected to the turbomolecular pump P3-1 through a high vacuum fluororubber sealing flange, the outlet of the molecular pump P3-1 is connected to the vacuum chamber C1-1 through a high vacuum fluororubber sealing flange, and the other end of the vacuum chamber C1-1 is connected to the air inlet of the direct-connected pump P6-1 and P6-2 through high vacuum pneumatic baffle valves V6-5 and V6-6 respectively. There are several front-stage exhaust branches 6.

[0033] The helium mass spectrometer leak detector 3 is connected to the vacuum chamber C1-1 through the high vacuum pneumatic baffle valve V6-1, and is used to analyze and find the size of the leak point on the vacuum chamber 7. The helium mass spectrometer leak detector 3 connected to the low vacuum side will significantly improve the system's minimum detectable leak rate compared to the high vacuum side.

[0034] In order to monitor whether the vacuum degree of the vacuum chamber 7 and the exhaust pipe meets the experimental operation requirements, the unit is equipped with several resistance gauges G1-1 and ionization gauges G2-1, measuring the vacuum range from 10 -5 Pa-10 5 Pa, uses ultra-high vacuum metal sealing flange to connect with vacuum pipe.

[0035] In order to ensure the reliability of the connection between the vacuum equipment and the connecting pipeline and meet both the mechanical installation requirements and the vacuum sealing requirements, the vacuum chamber 7 and the exhaust pipeline are connected with ultra-high vacuum metal sealing flanges, and the vacuum valve, vacuum pump and exhaust pipeline are connected with fluororubber sealing flanges.

[0036] Working principle of vacuum helium leak detection system for nuclear fusion reactor:

[0037] The main functions of the two Roots vacuum pumps P4-1, P4-2 and the two rotary vane pumps P5-1, P5-2 in the rough vacuum exhaust branch 5 are to exhaust the vacuum chamber 7 from atmospheric pressure to below 10Pa, so that the turbomolecular pump P1-1 has the starting working conditions, and then use them to exhaust the vacuum chamber C1-1 of the front-stage exhaust branch 6 to the normal working pressure range of the helium mass spectrometer leak detector 3, and use the helium mass spectrometer leak detector 3 to conduct qualitative analysis and quantitative detection of whether there are leaks in the vacuum chamber 7 that affect the experimental operation. The turbomolecular pump P3-1 and the direct-connected pumps P6-1, P6-2 in the front-stage exhaust branch 6 extract the gas extracted by the turbomolecular pump P1-1 in the main exhaust branch 4 into the atmosphere in stages.

[0038] The present invention adopts a turbo molecular pump P3-1 with a pumping speed of 3000 liters / second to connect with the helium mass spectrometer leak detector 3, which increases the flow rate of the leak detection tracer gas helium entering the helium mass spectrometer leak detector 3, so that the leak detection system reaction time is within 8 seconds. Then, the helium mass spectrometer leak detector 3 is used to perform qualitative analysis and quantitative detection on whether there are leaks in the vacuum chamber 7 that affect the experimental operation. The system can find out 10 leaks in the vacuum chamber 7 under test. -11 Pa﹒ 3 ﹒ -1 Leak rate of the leak.

[0039] If the vacuum pump unit is 42m 3 The fusion vacuum chamber 7 provides the initial working environment for vacuum leak detection. The unit is characterized in that the main exhaust system 1 includes four main exhaust branches 4. The four turbomolecular pumps P1-1, P1-2, P1-3, and P1-4 can provide an effective exhaust speed of 4800 liters per second, which can quickly exhaust the fusion vacuum chamber 7 to the required 10 vacuum chambers for leak detection. -5 Pa-10 -1 Pa vacuum environment.

[0040] The present invention also provides a leak detection method for a vacuum helium leak detection tool suitable for a nuclear fusion reaction device, the method comprising the following steps:

[0041] Step (1) Open the ultra-high vacuum pneumatic gate valve V1-1 and the ultra-high vacuum pneumatic gate valves V3-1 and V3-2, and start the rotary vane pumps P5-1 and P5-2 and the direct-connected pumps P6-1 and P6-2;

[0042] Step (2) When the vacuum degree of the vacuum chamber 7 is less than 1000 Pa, start the Roots vacuum pumps P4-1 and P4-2;

[0043] Step (3) When the vacuum degree of vacuum chamber 7 is less than 10Pa, start the turbomolecular pump P1-1, and when the vacuum degree of vacuum chamber C1-1 is less than 10Pa, start the turbomolecular pump P3-1, and when the main vacuum degree is less than 10-2Pa, open the ultra-high vacuum pneumatic gate valves V2-1 and V2-2, and close the Roots vacuum pumps P4-1 and P4-2 and the rotary vane pumps P5-1 and P5-2;

[0044] Step (4) starting the helium mass spectrometer leak detector 3, opening the high vacuum pneumatic damper valve V6-1 and calibrating the helium mass spectrometer leak detector 3;

[0045] Step (5) uses negative pressure blowing method to perform helium mass spectrometry leak detection on the vacuum chamber 7 to find tiny leaks in the vacuum chamber 7 body and connecting components caused by defects in the shell material of the vacuum chamber 7, installation deviation of the window device, electromagnetic force or plasma rupture during the experiment.

[0046] The present invention is described in detail above in conjunction with the embodiments, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of ordinary technicians in the field without departing from the purpose of the present invention. The contents not described in detail in the present invention can adopt the existing technology.

Claims

1. A vacuum helium leak detection tool suitable for a nuclear fusion reactor, characterized in that: The vacuum helium leak detection tool comprises a main exhaust system (1), a front-stage exhaust system (2), a helium mass spectrometer leak detector (3), a main exhaust branch (4), a rough vacuum exhaust branch (5) and a front-stage exhaust branch (6); The main air extraction system (1) comprises a plurality of main air extraction branches (4), each of which is connected in parallel. The main air extraction branch (4) comprises an ultra-high vacuum pneumatic gate valve V1-1, a turbomolecular pump P1-1, and a high vacuum pneumatic baffle valve V4-1. The front end of the ultra-high vacuum pneumatic gate valve V1-1 is connected to a vacuum chamber (7), and the rear end of the ultra-high vacuum pneumatic gate valve V1-1 is connected to the turbomolecular pump P1-1 and the high vacuum pneumatic baffle valve V4-1 in sequence. The front-stage exhaust system (2) comprises a rough vacuum exhaust branch (5) and a plurality of front-stage exhaust branches (6), each of which is connected in parallel, the rough vacuum exhaust branch (5) and the front-stage exhaust branch (6) are connected in parallel, the front end of the ultra-high vacuum pneumatic gate valve V2-1 of the front-stage exhaust branch (6) is connected to the rear end of the high vacuum pneumatic damper valve V4-1 of the main exhaust branch (4), and the ultra-high vacuum pneumatic gate valves V3-1 and V3-2 of the rough vacuum exhaust branch (5) are connected to the rear end of the high vacuum pneumatic damper valve V4-1 of the main exhaust branch (4); The helium mass spectrometer leak detector (3) is connected to the front-stage exhaust branch (6); The front ends of the two ultra-high vacuum pneumatic gate valves V3-1 and V3-2 in the rough vacuum exhaust branch (5) are respectively connected to the rear end of the high vacuum pneumatic baffle valve V4-1, and the rear ends of the ultra-high vacuum pneumatic gate valves V3-1 and V3-2 are respectively connected to the air inlets of two Roots vacuum pumps P4-1 and P4-2, and the air outlets of the Roots vacuum pumps P4-1 and P4-2 are respectively connected to the rotary vane pumps P5-1 and P5-2; The front end of the ultra-high vacuum pneumatic gate valve V2-1 of the front-stage exhaust branch (6) is connected to the rear end of the high vacuum pneumatic baffle valve V4-1 of the main exhaust branch (4), the rear end of the ultra-high vacuum pneumatic gate valve V2-1 is connected to the turbomolecular pump P3-1, the outlet of the molecular pump P3-1 is connected to the vacuum chamber C1-1, and the other end of the vacuum chamber C1-1 is connected to the air inlets of the direct-connected pumps P6-1 and P6-2 respectively through the high vacuum pneumatic baffle valves V6-5 and V6-6.

2. A vacuum helium leak detection tool suitable for a nuclear fusion reaction device according to claim 1, characterized in that: The helium mass spectrometer leak detector (3) is connected to the vacuum chamber C1-1 via a high vacuum pneumatic baffle valve V6-1 and is used to analyze the size of the leak point on the vacuum chamber (7).

3. A vacuum helium leak detection tool suitable for a nuclear fusion reaction device according to claim 2, characterized in that: The two Roots vacuum pumps P4-1, P4-2 and the two rotary vane pumps P5-1, P5-2 in the rough vacuum exhaust branch (5) evacuate the main vacuum chamber (7) from atmospheric pressure to below 10 Pa, so that the turbomolecular pump P1-1 has the conditions for starting working.

4. A vacuum helium leak detection tool suitable for a nuclear fusion reaction device according to claim 3, characterized in that: The turbomolecular pump P3-1 and the directly connected pumps P6-1 and P6-2 in the front-stage exhaust branch (6) extract the gas extracted by the turbomolecular pump P1-1 in the main exhaust branch (4) into the atmosphere in stages.

5. A leak detection method for a vacuum helium leak detection tool suitable for a nuclear fusion reaction device according to claim 4, characterized in that: The method comprises the following steps: Step (1) Open the ultra-high vacuum pneumatic gate valve V1-1 and the ultra-high vacuum pneumatic gate valves V3-1 and V3-2, and start the rotary vane pumps P5-1 and P5-2 and the direct-connected pumps P6-1 and P6-2; Step (2) When the vacuum degree of the vacuum chamber (7) is less than 1000 Pa, start the Roots vacuum pumps P4-1 and P4-2; Step (3) When the vacuum degree of the vacuum chamber (7) is less than 10Pa, start the turbomolecular pump P1-1, and when the vacuum degree of the vacuum chamber C1-1 is less than 10Pa, start the turbomolecular pump P3-1, and when the main vacuum degree is less than 10-2Pa, open the ultra-high vacuum pneumatic gate valves V2-1 and V2-2, and close the Roots vacuum pumps P4-1 and P4-2 and the rotary vane pumps P5-1 and P5-2; Step (4) starting the helium mass spectrometer leak detector (3), opening the high vacuum pneumatic damper valve V6-1 and calibrating the helium mass spectrometer leak detector (3); Step (5) uses a negative pressure blowing method to perform helium mass spectrometry leak detection on the vacuum chamber (7) to find tiny leak points.

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