Leak Testing Flashcards
Equivalent to pressure times volume divided by time
Leakage rate
Unit measure for leakage rate
SI
Term requires at the leakage flow be too small to be detected
Leaktight
A measure of concentration or flow rate of tracer gas that gives a minimal measurement leak signal
Leak detector sensitivity
Refers to the minimum detectable amount of leakage that will occur in the specific period of time under specified leak test conditions
Leak test sensitivity
Leak testing can be divided into three main categories:
Leak detection, leak location, and leak measurement
Two classifications of leakage rate measurement techniques involving the use of tracer gases are
Static and dynamic leak testing
The chamber into which the trace gas leaks in accumulates is sealed and is not subjected to pumping to remove the accumulated gases
Static leak testing
The chamber into which tracer gas leaks is pump continuously and intermittently to draw the leaking tracer gas through the leak detector instrumentation
Dynamic leak testing
Directs sniffing with no significant halogen contamination in the atmosphere
Method A
Direct sniffing with significant halogen contamination in the atmosphere
Method B
Shroud test (halogen leak testing)
Method C
Accumulation test
Method E
Air curtain shroud test
Method D
Mode of gas flow that occurs in leaks leaking at atmospheric or higher pressure under pressure testing conditions
Viscous flow
Mode gas flow that usually occurs in leaks under vacuum testing conditions
Molecular flow
Mode of gas flow that occurs under test conditions immediate between vacuum and pressures higher than atmospheric pressure
Transitional flow
The most sensitive leak testing technique is
Mass spectrometer test
Leak testing establishes differential pressure’s between
Test object and environment
Assuming no significant leakage, if the temperature increased during a pressure dropped leak test, the pressure in the system under the test would
Increase
If the sensitivity of the halogen leak detector is constant throughout the test then
The instrument in test procedure were capable of detecting leakage of a certain size during the test
All leak detection methods are dependent upon
Gas or fluid flow
The release of gas for materials in a vacuum is best defined as
Outgassing
Used for leak location and leak rate
Halogen diode detector
This property would not affect the performance of a bubble solution
Contrast
