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
  • G01M3/205—Accessories or associated equipment; Pump constructions
• • 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
  • G01M3/207—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 calibration arrangements
• • 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
  • G01M3/22—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 for pipes, cables or tubes; for pipe joints or seals; for valves; for welds; for containers, e.g. radiators
  • G01M3/226—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 for pipes, cables or tubes; for pipe joints or seals; for valves; for welds; for containers, e.g. radiators for containers, e.g. radiators

Definitions

• the invention relates to a device and a method for gas leak detection with a Testgassprühvorraum.
• the vacuum arrangement in this case has a vacuum pump for evacuating the test specimen and a gas detector for detecting the proportion of test gas in the evacuated gas flow. If the sample has a leak and the test gas stream dispensed by the spray gun approaches the leak, the proportion of test gas in the evacuated gas stream increases. The increase in the proportion of test gas in the evacuated gas flow is understood as an indication that the spray gun is approaching a leak in the test specimen.
• the spray gun may for example be a compressed air gun which is connected via a hose with a test gas pressure cylinder or with a filled with the test gas rubber bladder.
• a compressed air gun which is connected via a hose with a test gas pressure cylinder or with a filled with the test gas rubber bladder.
• the pressure on the compressed air gun and thus the flow rate through a pressure reducer in the gas cylinder is set.
• the device according to the invention is defined by the features of claim 1.
• the method according to the invention is defined by the features of claim 5.
• the spraying device is designed to detect at least one point in time of the spraying process, for example the start of spraying.
• the times recorded by the spray device and the at least one point in time of the spraying process can be transmitted to the evaluation unit via the data communication connection.
• the evaluation unit is designed to correlate the times transmitted by the spraying device with the respective measuring signal. This makes it possible to detect whether the increase in the test gas partial pressure in the measurement signal is caused by spraying with the test gas spray gun.
• the time of the end of the test gas spray is also transmitted from the spray device to the evaluation unit and correlated with the measurement signal in the evaluation unit.
• the spray device may be a spray gun which is connected via a hose to a compressed gas source containing the test gas.
• the spray device generates a series of several short test gas pulses, that is, the test gas is pulsed output from the spray device.
• the test gas is pulsed output from the spray device.
• at least the time of the beginning of a pulse train is transmitted to the evaluation unit and preferably also the times of the respective end of a test gas pulse train.
• the duration of the test gas delivery can also be recorded electronically and transmitted to the evaluation unit.
• the application of the test gas in a particular pulse sequence may allow differentiation of interfering test gas background concentrations, as these are constant or at least slowly variable, while a test gas entering the sample through a leak can only enter from the spray device during spraying.
• the measurement signal or the time profile of the measurement signal can also be transmitted from the evaluation unit to the spraying device or to an output device, for example a monitor, arranged in the vicinity of the spraying device.
• the invention is thus based on the idea of detecting times of the spraying action with the spraying device and of transmitting them to the evaluation unit in order to correlate the measuring signal with the spraying times.
• a spray gun 12 is connected via a compressed air hose 14 and a shut-off valve 16 to a pressurized helium source 18.
• the shut-off valve 16 may alternatively be arranged in the spray gun 12.
• the helium is the test gas with which the test piece 20 is sprayed to detect and locate a leak on the test piece.
• the test object 20 is connected via a gas-conducting connection 22 via a shut-off valve 24 to a vacuum pump 26 for evacuating the test object 20. Downstream of the vacuum pump 26, a gas detector in the form of a mass spectrometer 28 is arranged. The mass spectrometer determines the helium partial pressure in the gas stream extracted from the test specimen 20. The elements 22, 24, 26, 28 form a vacuum arrangement 30. The mass spectrometer 28 is connected to an evaluation unit 32, which continuously evaluates and displays the measurement signal.
• a data communication connection 34 between the spray gun 12 and the evaluation unit 32 is shown in dashed lines.
• This can be a wireless connection, for example radio, WLAN, infrared, Bluetooth, or a wired data connection.
• 32 times are transmitted at least from the spray gun 12 to the evaluation unit, namely at least the time of the start of spraying and preferably also the duration of spraying and the time of spraying.
• a pulsed spray that can be controlled via the valve 16
• the beginning of the spray, the duration and the spray end of each spray pulse or of the spray pulse series are transmitted to the evaluation unit 32.
• the evaluation unit 32 transmits the measurement signals to an output unit connected to the spray gun 12 or arranged in the vicinity of the spray gun 12 (not shown in the figure). This makes it possible for the user to have a simple view of the measurement results and to modify the spray action accordingly. Once the user detects an increase in helium concentration, he can selectively direct the spray gun 12 in the required direction to determine the spray location to produce the maximum leakage signal.
• the measurement signal can be transmitted via the data connection 34 to a smartphone or a tablet PC.
• the vacuum assembly 30 may be a helium vacuum leak detector connected to the test object 20.
• the connection point may be the fore-vacuum region of a multi-stage pumping system on the test sample. Alternatively, the connection can also be made directly to the vacuum chamber or the exhaust of the backing pump of the pumping system.
• the reaction time - the vacuum time constant - of the system is determined.
• a spray-on pen leak is to be flanged to the vacuum chamber to be checked. This is permanently sprayed with helium, during which the signal is detected by the leak detector. The pen leak is sprayed until a stable signal is displayed on the leak detector.
• the vacuum time constant of the system can be determined.
• the time constant may be determined from the decay curve measured after the completion of helium spraying. Typical time constants of plants are in the range of 1 to 10 seconds and are sometimes significantly longer.
• a spraying process consists of several successive spray pulses.
• the duration of the helium spray pulses and the time interval between the pulses can be determined.
• the duration of the pulses and the time interval of the pulses should be about half a vacuum time constant or less.
• pulse durations of 1/10 or less are selected.
• the number of spray pulses per spray should be about three to five.
• the duration between the individual pulses can be different. The more characteristic the pulse sequence is, the better the signal sequence at the leak detector can be recognized in the event of a leak.
• the vacuum chamber is sprayed at the inspection sites to locate leaks.
• the pulse sequence which is characterized by helium spraying, is transmitted during the spraying of a leak to the time profile of the measured leakage rate signal. Disturbances of the signal due to drift, noise or other causes, which do not exhibit this pulse train pattern, or occur too early or too late with respect to the time of spraying, can thus be distinguished from true leak rate signals in the signal evaluation.
• the helium can be actively blown between the helium pulses, eg with a cyclically starting fan on the spray gun.
• the operator gets the result directly at the test site and does not need any direct contact with the measuring device (the vacuum leak detector).
• the operator may be provided with recommendations on spray behavior to the spray gun via the data link 34.
• the leak detection is feasible with only one person.
• the carrying of heavy helium bottles can be omitted. Helium consumption can be reduced.
• a compact design with improved accessibility is possible. Faulty settings of the spray gun, such as too much or too little helium, can be prevented.
• To optimize the spraying process a lot of helium can be sprayed for localization and then less helium can be sprayed for quantification.

Priority Applications (1)

Applications Claiming Priority (2)

Related Child Applications (1)

Publications (1)

Family

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Family Applications (2)

Family Applications Before (1)

Country Status (9)

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Family Cites Families (17)

• 2016
  • 2016-03-31 DE DE102016205381.7A patent/DE102016205381B4/de active Active
• 2017
  • 2017-03-28 KR KR1020187028523A patent/KR102377323B1/ko active IP Right Grant
  • 2017-03-28 CN CN201780021497.7A patent/CN109073495B/zh active Active
  • 2017-03-28 EP EP20186105.1A patent/EP3742148B1/de active Active
  • 2017-03-28 WO PCT/EP2017/057294 patent/WO2017167738A1/de active Application Filing
  • 2017-03-28 RU RU2018137195A patent/RU2728802C2/ru active
  • 2017-03-28 JP JP2018551121A patent/JP6862472B2/ja active Active
  • 2017-03-28 US US16/089,665 patent/US10837857B2/en active Active
  • 2017-03-28 EP EP17713949.0A patent/EP3436793A1/de not_active Ceased
  • 2017-03-29 TW TW106110623A patent/TWI730076B/zh active

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