Millipore Integritest Exacta, Operating And Maintenance Manual

Page: 107 / 284

Millipore System Documentation Set
108
Operating and Maintenance Manual Publication XITXSP121 P Rev.A
TEST PROCEDURES OF THE INTEGRITEST EXACTA INSTRUMENT
Diffusion Test Steps:
1. System check
2. Clear housing of excess fluid
•
Apply ½ of the test pressure to the housing.
3. Determine upstream gas volume
4. Pressurize the system to the test pressure
•
Allow the pressure to stabilize
5. Run Pressure Decay Test
•
Measure pressure loss due to gas flow through the filter
6. Determine diffusion flow
•
Calculate normalized diffusion constant (gas flow as a function of pressure).
•
When the diffusion constant (and therefore the diffusion flow rate) stabilizes, end
diffusion test.
Note: The diffusion flow rate determination is stabilization driven, not event (i.e., Time)
driven.
Bubble Point Test Steps
1. System check
2. Clear housing of excess fluid
3. Determine upstream volume
4. Pressurize the system to the diffusion test pressure (or 80% of the bubble point
specification if the diffusion test pressure was not entered into the filter editor)
•
Allow the pressure to stabilize.
•
Increment pressure until bubble point is determined.
-
Increase pressure to 1 psi below the bubble point specification.
-
Increase pressure in 1 psi increments until 1 psi above the bubble point specification.
-
Increase pressure in increments proportional to 2.5 psi (1 psi for IPA tests) until bubble
point is reached. This proportionally reduces the step size as pressure gets further away
from the minimum bubble point specification.
-
Increase pressure in various increments above the bubble point until the test is complete.
5. Calculate decay
•
Calculate pressure loss after each pressure-decay period.
6. Continue testing
•
The instrument determines changes in flow by an Intersection of Tangents method.
The intersection between the diffusion curve and a linear fit of the flowrates above
the bubble point is defined as the bubble point.
Enhanced Bubble Point Test Steps
The Enhanced Bubble Point test is a combination of the diffusion and bubble point tests.
1. System check
2. Clear housing of excess fluid