Preventive Maintenance
Packed column inlet
4.Fully open the mass flow controller counterclockwise and wait 1 to 2 minutes to ensure equilibrium.
5.Turn off gas to the inlet at its source.
6.Wait 10 minutes while observing carrier source pressure. If it drops less than 7 to 14 kPa (1 to 2 psi), the system (through the inlet column fitting) is considered leak free.
Evidence of leakage requires the inlet system be leak•checked.
Repressurize the system as necessary, and
CUse a suitable leak•detectionfluid to check for leakage fittings. Correct or replace leaking fittings as needed.
Caution | Leak•detectionfluids often leave contaminating residues; after each |
| application, the area checked should be rinsed with CH3OH (methanol) |
| and allowed to dry. |
CAfter verifying fittings are leak•free,there are two locations at the inlet itself where leakage may occur: at the septum, and at the column connection.
-The column connection is checked using a leak•detectionfluid.
-The septum is checked with a bubble flow meter by pressing its rubber inlet tube tightly onto the needle entrance in the septum retainer nut or simply replacing the septum.
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