1、Leak Detector WorkshopAgenda Definition Methods of Leak Detection Principles of Leak Detectors Overview of INFICON L.D.How to perform a leak check DefinitionWhat is a leak rate?The leak rate states the quantity of gas which flows through a leaking point at a given pressure difference.Unit:mbar l s-1
2、 Pressure gauge Point of the leak VW=1l qPVDefinitionDiameterequals helium leak rate(mbar I/s)1.0 cm 10+41.0 mm 10+20.1 mm 10 00.01 mm 10-21.0 m 10-4 1.0 Angstrom 10-12DefinitionPressure Rise/ROR testQ=VP/tLeak CheckWhy use Helium as a test gas?Excellent separation within a mass spectrometer from ne
3、ighboring masses Only 5 ppm in the air-a very low background Smallest gas particle except hydrogen Inert gas-does not react with other substances Non-toxic,non-combustible,non-explosive lighter than air-it aids leak testing,as the test gas may escape upwards inexpensiveDefinitionMethods of Leak Dete
4、ctionMethods of Leak DetectionVacuum Methods:The equipment to be tested is evacuated.(1)Local leak detection:Evacuated test sample&Helium is sprayed on from the outside.Time Constants(2)Integral leak detection:Evacuated test sample&Test sample within a helium atmosphereMethods of Leak DetectionOverp
5、ressure Method:The equipment to be tested is pressurized with a search gas.(1)Local leak detection:Test sample contains heliumMethods of Leak Detection(2)Integral leak detection:Test sample contains helium,test sample was in an evacuated container Methods of Leak DetectionWhere to connect a Leak Det
6、ector Methods of Leak DetectionPrinciples of Leak DetectorPrinciples of Leak DetectorA helium leak detector measures the helium partial pressure in the pump line and converts it into a leak rate.QHe=PHe x SHeHe Pumping SpeedHe Partial PressureLeak RatePrinciples of Leak DetectorSelective Mass Spectr
7、ometer(1)magnetic field(perpendicular to ion path)(2)positive ions(all masses)(3)ion collector(4)ampere meter and amplifier(5)accelerating voltage(6)anode(7)electrons(8)heated filament(iridium/yttrium coated)P.S:hydrogen atoms/ions(red color)P.S:helium atoms/ions(green color)P.S:heavy atoms/ions(blu
8、e color)Overview of INFICON L.D.UL1000 FabUL1000 FabUL1000 Fab Technical IssuesPower ON:Scroll pump ONPower ON:Scroll pump ONV2 OpenTMP ONPower ON:Scroll pump ONV2 OpenTMP ONPower ON:Scroll pump ONV2 OpenTMP ONEmission ONPower ON:Scroll pump ONV2 OpenEvacuation Mode:V2 OFFEvacuation Mode:V2 OFFV1a,V
9、1b openEvacuation Mode:V2 OFFV1a,V1b openEvacuation Mode:V2 OFFV1a,V1b openUL1000 Fab Technical IssuesGross Mode:V1a,V1b,V2 openInlet pressure:15 mbarHe-pumping speed at inlet port:3.8 l/sDetection limit:1x10-7 mbar l/sUL1000 Fab Technical IssuesFine ModeV4a,V2 openInlet pressure:2 mbarHe-pumping sp
10、eed at inlet port:1.5 l/sDetection limit:1x10-10 mbar l/sUL1000 Fab Technical IssuesUltra ModeV4b,V2 openInlet pressure:0,4 mbarPumping speed:2.5 l/sDetection limit:1x10-12 mbar l/sUL1000 Fab ZERO function 1x10-101x10-91x10-81x10-61x10-121x10-71x10-51x10-101x10-91x10-81x10-61x10-71x10-51x10-101x10-9
11、1x10-81x10-61x10-71x10-51x10-101x10-91x10-81x10-61x10-71x10-51x10-111x10-11GROSSFINEULTRAUL200/UL500UL1000 FabP0.3 TorrTo perform a Leak Check準備測漏準備測漏l1 米長的 25KF 軟管l25/40 KF,25/16 KF 轉接頭l25KF center ring,clamp,40KF center ring,clamp,16KF center ring,clampl25 KF blank l氦氣及噴槍l電源延長線l大型真空包裝袋l小型真空包裝袋l真空矽膠或真空黏土lIPA 或 酒精l裝 DI water 之小容器(小杯子)l擦拭布l測漏儀l外接式標準漏或微漏件或乾淨之細髮調整氦氣流量調整氦氣流量DI Water連接測漏儀連接測漏儀量測反應時間量測反應時間開始測漏開始測漏開始測漏開始測漏不恰當的測漏法不恰當的測漏法 End
