STUDY ON PROPERTY OF CALIBRATING VACAUUM LEAK DEVICE WITH CONSTANT CONDUCTANCE METHOD

Constant conductance method uses quardrupole mass spectrometer to compare the known gas out of conduction orifice with gas from vacuum leak,It is a very precise method to deal with leak rate.Orifice is the use of machinery,laser processing method for producing,In the molecular flow conditions,the orifice conductance is a constant.Use this method for calibration data,we found a standard vacuum leak detection.To ensure the credibility of calibration data,the uncertainties of calibration system should be precisely estimated.