Degas Valves - Micromeritics ASAP 2020 Confirm Operator's Manual

Appendix D

Degas Valves

Perform the following steps to measure the degas manifold outgas rate.
1. Ensure that the degas system is idle.
2. Close the regulator outlet valve for the backfill gas.
3. Insert a plug (or attach a clean, empty sample tube) into each degas port.
4. Select Degas, Show Degas Schematic, then Degas, Enable Manual Control from the
Unit menu. (For clarity, this illustration shows only the valve portion of the schematic.)
Table D-2 lists descriptions of the degas valves.
5. Open Valves D5, D1, D2, and then D7.
6. Open Valve D6.
7. Allow the degas system to evacuate below 10 mHg, then evacuate for 60 minutes.
8. Close Valves D1, D2, D5, D6, and D7.
9. Take a pressure reading and record it as P1 for the preliminary test.
10. Wait 10 minutes and take another reading; record it as P2 for the preliminary test.
11. Subtract P1 from P2 and divide the difference by 10; record this value as the outgassing
rate for the preliminary test. This value should be less than 10 mHg/min.
202-42811-01 - Mar 2011
Table D-2. Degas Valve Descriptions
Valve
D1 and D2 Degas port valves
D5 Vacuum valve
D6 Servo isolation valve
D7 Gas inlet port valve
ASAP 2020 Confirm
Description
D-7