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Through-Put Test

The purpose of the through-put test is to check the rate of flow of the mixture through the lines. The ideal flow rate is ~ 45 mbar/min. If it's too low, this indicates a blockage in the lines somewhere, which might be corrected by cleaning the cold traps and/or the mixture.

  1. Turn on the leak checker to warm it up for 20 minutes. Make sure the calibration is ne. Once the leak checker is warmed, start the leak check and get a background reading - record it in the run diary.
  2. Pump mixture into dump.
  3. Close all valves on IGH.
  4. Open gate valve and condenser line speedivalve.
  5. Pull up the LabVIEW plots that monitor the pressures in G1 and G2. If the IGH Front Panel vi is not already up on the DAQ computer:
    1. Go to I:/LabVIEW.
    2. Click on the shortcut to StartUp.vi.
    3. Select 'Applications'.
    4. Click on \IGH Front Panel“.
    5. To open the plots, click on 'Kelvinox'.
    6. Click on \Monitor”.
  6. Open V3, V14, V9; this lets mixture out of the dump and settle in the lines, so wait for G1 and G2 to stabilize.
  7. At the first sign that G1 and G2 have stabilized, close V14 and V3; open V1 immediately after.
  8. Monitor pressure rise in G1 using the pressure plots. If the rate is not around 45 mbar/minute, redo the test. Try to remember how quickly or slowly you closed V14 and V3. This may have affected your results. Now that you've seen at what value G1 and G2 should stabilize at, you are better prepared on when to close V14 and V3 when you redo the test.
  9. To repeat the test, pump the mixture back into the dump. Close V6 first, and once it is nished closing, then close V1, V5, and V9. Then perform the above steps again.
  10. If the rate is still inappropriate there may be a blockage in the system, which means you will have to clean the cold traps. See appendix for cleaning instructions.
  11. When conducting the throughput test, check the leak rate. Record the value in the run diary.
  12. When done performing the throughput test, record the flow rate in the run diary. Pump the mixture to the dump.
  13. Close the gate and condenser valves. Close all of the valves on the IGH.