Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
  • G01M3/00—Investigating fluid-tightness of structures
  • G01M3/02—Investigating fluid-tightness of structures by using fluid or vacuum
  • G01M3/04—Investigating fluid-tightness of structures by using fluid or vacuum by detecting the presence of fluid at the leakage point
  • G01M3/20—Investigating fluid-tightness of structures by using fluid or vacuum by detecting the presence of fluid at the leakage point using special tracer materials, e.g. dye, fluorescent material, radioactive material
  • G01M3/202—Investigating fluid-tightness of structures by using fluid or vacuum by detecting the presence of fluid at the leakage point using special tracer materials, e.g. dye, fluorescent material, radioactive material using mass spectrometer detection systems
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D65/00—Accessories or auxiliary operations, in general, for separation processes or apparatus using semi-permeable membranes
  • B01D65/10—Testing of membranes or membrane apparatus; Detecting or repairing leaks
  • B01D65/104—Detection of leaks in membrane apparatus or modules
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
  • B01D71/02—Inorganic material
  • B01D71/022—Metals
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
  • B01D71/02—Inorganic material
  • B01D71/022—Metals
  • B01D71/0223—Group 8, 9 or 10 metals
  • B01D71/02231—Palladium
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
  • B01D71/02—Inorganic material
  • B01D71/024—Oxides
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
  • G01L27/00—Testing or calibrating of apparatus for measuring fluid pressure
  • G01L27/002—Calibrating, i.e. establishing true relation between transducer output value and value to be measured, zeroing, linearising or span error determination
  • G01L27/005—Apparatus for calibrating pressure sensors
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
  • G01M3/00—Investigating fluid-tightness of structures
  • G01M3/007—Leak detector calibration, standard leaks
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
  • G01M3/00—Investigating fluid-tightness of structures
  • G01M3/02—Investigating fluid-tightness of structures by using fluid or vacuum
  • G01M3/04—Investigating fluid-tightness of structures by using fluid or vacuum by detecting the presence of fluid at the leakage point
  • G01M3/20—Investigating fluid-tightness of structures by using fluid or vacuum by detecting the presence of fluid at the leakage point using special tracer materials, e.g. dye, fluorescent material, radioactive material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2325/00—Details relating to properties of membranes
  • B01D2325/04—Characteristic thickness

Definitions

• the invention relates to a vacuum leak detector with a test leak and a method for testing the functionality of a leak detector.
• Leak detectors which enable leaks to be found with test gas, are used to check the tightness or to detect leaks on test objects using the test gas vacuum method.
• the objects to be tested can be, for example, vacuum furnaces, production systems with vacuum chambers in the semiconductor industry, pipelines of various types or other chambers.
• the test item is evacuated for the leak test. The evacuation can be carried out with the pump system assigned to the test object or with a separate pump system which is provided with the leak detector.
• a tracer gas detector is integrated into the leak detector, eg a mass spectrometer, with which the tracer gas can be detected.
• the test gas can be, for example, helium or forming gas (95% nitrogen + 5% hydrogen).
• the areas to be tested e.g. flange seals, weld seams, ...) are sprayed with the test gas on the atmospheric side of the test item. If there is a leakage channel at the sprayed point, the test gas flows together with the ambient air through the leakage channel into the vacuum chamber and on to the vacuum system.
• the test gas can be detected with the detection system (e.g. mass spectrometer).
• the signal strength is a measure of the leak rate and the temporal correlation of spray location and time and signal response is an indication of the leak location.
• WO 2006/120122 A1 describes a sniffer leak detector in which the test gas inlet has a quartz window sensor. A test leak is not provided there.
• capillary leaks are used as test leaks in sniffer leak detectors of the type described in WO 2006/120122 A1, with the test or test gas flowing out of the test leak to the atmosphere being sucked up and detected using a so-called sniffer probe.
• the object of the invention is to provide a vacuum leak detector with an improved test leak and to enable a corresponding leak detection method.
• the vacuum leak detector according to the invention is defined by the features of patent claim 1.
• the leak detection method according to the invention is defined by the features of patent claim 11.
• a test leak connecting the outer atmosphere of the housing with the suction chamber is provided with a selectively gas-permeable membrane on the housing enclosing the suction chamber of the vacuum leak detector, which is connected to a vacuum pump evacuating the suction chamber and a gas detector connected to the suction chamber.
• the Test leak sprayed with a test gas in such a way that the test gas selectively passes through the membrane into the interior of the suction chamber, while air or atmospheric gases from the area surrounding the vacuum leak detector are blocked by the membrane.
• the test gas that has entered the suction chamber through the membrane is detected with the gas detector.
• the membrane according to the invention makes it possible to determine whether the measurement signal of the test gas measured with the gas detector corresponds to the measurement signal to be expected given unrestricted functioning of the vacuum leak detector.
• the functionality of a vacuum leak detector can be tested in a simple manner with the aid of the invention.
• the spray gas source with which the test gas is applied works properly, i.e. that it delivers the desired type of test gas in sufficient quantity.
• test leak can be designed as a spray leak in order to selectively direct test gas sprayed onto the test leak from the outside through the membrane into the suction chamber, while gases other than the test gas are blocked.
• the membrane of the test leak can have quartz for the selective passage of helium, neon or hydrogen or can be made of quartz. Alternatively or additionally, the membrane can contain or consist of palladium for the selective passage of hydrogen and/or silver for the selective passage of oxygen.
• the material of the membrane can be in the form of a thin-walled, closed tube, for example in the form of a glass finger.
• the membrane material can be designed to selectively conduct or block the test gas depending on the temperature, while a heater is provided for heating the membrane.
• the membrane can have a layer thickness of a few micrometers and preferably a maximum of about 100 ⁇ m.
• the test leak can have a holder for the membrane inserted into an opening of the housing in the manner of a flange.
• the holder can preferably be covered by a protective grid on its outside and/or its inside.
• the test leak can have a plurality of channels each closed by one or the selectively gas-permeable membrane.
• the membrane can be attached to a membrane chip, the membrane chip having a thickness of preferably less than one centimeter and particularly preferably less than one millimeter.
• the membrane chip has a membrane-covered membrane window, which is designed as a channel that completely penetrates the membrane chip and has a maximum diameter of about 1000 ⁇ m and at least about 10 ⁇ m, so that one end of the channel is covered by the membrane .
• the membrane preferably closes off the duct on the atmosphere side, i.e. it covers the end of the duct opposite the suction chamber, so that no water vapor or dirt particles from the environment can enter the duct.
• the membrane can be attached to a membrane chip, which has at least one membrane window covered by the membrane and has a thickness of preferably less than 1 mm.
• the membrane window is preferably supported by an open-pore porous structure, such as. B. a grid or a porous solid material to support and stabilize the membrane.
• a selective gas inlet is provided on the leak detector vacuum system.
• the selective gas inlet is realized with a membrane that is tight or almost impermeable to atmospheric gases. That's not how the vacuum system works existing test gas unaffected.
• tracer gas is sprayed onto the membrane spray leak, the tracer gas permeates through the membrane into the vacuum system and is detected there with the detection system, which confirms the functionality of the overall system (detection system) and tracer gas spray source.
• Suitable membrane materials can be selected depending on the test gas used:
• the material can be designed as a thin-walled, closed tube (glass finger).
• the material must be heated so that the diffusion rate of the gas through the separating layer is sufficiently rapid.
• the configuration as a thin membrane a few micrometers thick, it is sufficient to use the membrane at room temperature in order to obtain a sufficiently rapid reaction.
• Fig. 2 shows a detail from Fig. 1 and
• Fig. 3 shows a detail from Fig. 2.
• the vacuum leak detector 10 shown has a housing 14 surrounding a suction chamber 12 and which is connected in a gas-conducting manner by a vacuum line 16 to a gas detector 18 and a vacuum pump 20 .
• the housing 14 has a test gas inlet 22 through which the test gas to be tested is drawn in from the external environment 24 of the housing 14 into the suction chamber 12 in order to be analyzed by the gas detector 18 .
• the housing 14 is provided with a test leak 26 which completely covers an opening in the housing 14.
• the test leak 26 is shown in more detail in FIG. 2 in an exploded view.
• the test leak 26 has a holder 28 in the manner of a flange, which fits completely into the associated opening of the housing 14 and closes it with a seal.
• the holder 28 is designed as a circular disk, in the region of whose center a recess 30 is designed.
• a hole through the bracket 28 is formed at the bottom of the recess 30 .
• a selectively gas-permeable membrane is inserted into the depression 30 as a membrane chip 32, which completely and gas-tightly covers the hole in the bottom of the depression 30.
• the membrane 32 is selectively gas permeable to a particular type of gas and blocks all other types of gas.
• the upper side of the holder 28 pointing in the direction of the external environment 24 and the underside of the holder 28 pointing in the direction of the suction chamber 12 are each covered by a protective grid which completely covers the depression 30 with the membrane 32 and the hole covered by the membrane 32. Both protective grids 34 are firmly screwed to the holder 28 with the aid of screw connections.
• the membrane 32 is in the form of a quartz membrane chip and has approximately 50 holes in the center which are in the form of channels and pass completely through the membrane chip 32 36 provided, which are arranged in a grid with equal distances from each other.
• Each of the holes 36 is closed by a quartz membrane approximately 10 ⁇ m thick.
• the thickness of the membrane chip 32 is about 0.6 mm.
• Each of the holes 36 forms a quartz window which is selectively gas permeable to helium at a membrane temperature of about 25° C., while other gases contained in air do not pass through the membrane 32.
• helium only neon and hydrogen permeate through quartz, but only to a lesser extent than helium, so they can also be used as a test gas when using the spray leak with a quartz membrane.
• the protective grid 34 protects the membrane chip 32 from direct contact, for example with a spray gun 38 when the spray gun, as shown in FIG. 1, sprays helium 40 onto the test leak 26 in the direction of the arrow in FIG.

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• Chemical & Material Sciences (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Inorganic Chemistry (AREA)
• Analytical Chemistry (AREA)
• Examining Or Testing Airtightness (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=84604283

Family Applications (1)

Country Status (8)

Families Citing this family (1)

Family Cites Families (12)

• 2021
  • 2021-12-23 DE DE102021134647.9A patent/DE102021134647A1/de active Pending
• 2022
  • 2022-12-16 TW TW111148381A patent/TW202326089A/zh unknown
  • 2022-12-22 US US18/723,123 patent/US20250058284A1/en active Pending
  • 2022-12-22 JP JP2024536147A patent/JP2024545812A/ja active Pending
  • 2022-12-22 EP EP22830278.2A patent/EP4453529A1/de active Pending
  • 2022-12-22 WO PCT/EP2022/087584 patent/WO2023118490A1/de not_active Ceased
  • 2022-12-22 CN CN202280083782.2A patent/CN118556179A/zh active Pending
  • 2022-12-22 KR KR1020247016346A patent/KR20240127332A/ko active Pending

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