|
|
|
|
|
|
|
 |
|
 |
|
Leak Test Methods
|
|
|
|
|
Pressure part with air under water
- Relatively inexpensive for most parts
- Allows location of leak to be determined
- Does not quantify leak rate
- Operator dependent
- Parts are wet, often requiring additional drying operation
|
|
 |
|
 |
|
 |
|
|
Pressure decay/differential pressure
- Moderate cost air leak test method
- Can provide accurate results with long test imes
- Long test itmes compared to mass flow
- Indirect calculation of leak rate based on pressure drop
- Leak values are both volume dependent and tine dependent
|
|
 |
|
 |
|
|
|
|
|
|
Mass flow and differential mass flow
- Direct measurement of leak rate
- Not time or pressure dependent
- Allows for meaningful graphic display of leak/flow vs time
- Requires reference part for differential mass flow
|
|
Setup, Calibrate, Test.....
|
|
 |
|
Helium mass spectrometer
- Can detect very small leaks in large parts
- Can provide accurate results in short test times
- High capital cost (often 10 times air leak test methods)
- High maintenance cost including consumables
|
|
|
|
Other leak test methods such as sniffers, and ultrasonic detection are used in limited applications.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|