The procedure written by Jordan Bohn (docdb 10337 ) needs to be updated.
Note: The reason behind leaving EV-200-N, and EV-102-N valves OPEN after a fill is to let any residual LN2 vent out without letting cryogenics (LN2) trap inside the piping. Those relevant valves let 'cooling down' the piping (pre-cooling the line), as a preparation step.
Magnet Shield Fill: Routine Fill
Checklist:
- On QT-HMI ODH page ensure LL-106-N is reading the shield level and that it shows < 75%.
- PT-106-N is below 15 psig (shield relieves at 35 psi, pay attention to not exceed that value).
- PT-110-N reads a value between 20psig-65psig.
- Ensure EV-200-N is closed. It may have been left open earlier since the purifier was filled. If it is left open, then leave it open and then close it after Step #2 below.
- Ensure VNFA on the purifier overview LN2 is CLOSED.
- LN2 tank (Tank #54) outside has > 20 inwc level.
- HCV13 (hand-valve at the tank) is CRACKED OPEN to about 1/2 turns from the fully closed position (on 12/22/2023 we decided to leave it at this position).
- Note down the start time and the initial level for the elog entry.
Steps:
- Open EV-102-N.
- Open EV-100-N. (Then close EV-200-N if it was left open until now).
- Monitor TE-104-N, TE-107-N, TE-108-N, and they should reach < 90 Kelvin.
- TE-108-N does not go below 150 K, as of 2024-01-01.
- When the temperatures reaches below 90 Kelvin, Open EV-105-N to 24% or 26% (input '24' + press 'Enter') to maintain the PT-106-N at 30 psig.
You can see a number-pad appear on the screen to enter the value for the opening of EV-105-N. Enter the number, and remember to press the "ENTER" key.
- Close EV-102-N.
- Monitor PT-106-N and ensure it doesn't stay at the top value of 30 psig.
- Adjust EV-105-N (usually by +-1...2%) to keep PT-106-N around/below 30 psig.
- If the pressure doesn't fall back below 30 psig, then STOP the filling by Closing EV-100-N and Opening EV-102-N, then Close EV-105-N (input '0' + press 'Enter'). Note: If PT-106-N increases to 35 psig, then PRV401 will vent at 35 psig in the cave we need to avoid.
- Monitor LL-106-N reaching 90%.
- Close EV-100-N.
- Open EV-102-N.
- Close EV-105-N (input '0' + press 'Enter').
- Note down the finish time the and final level for the elog entry.
- Post a Fermilab elog entry regarding this fill (see the past elog entries for the format)
- After ~4 hrs, ensure TE-104-N, TE-107-N, TE-108-N are at room temperature and then Close EV-102-N.
Warm Magnet Shield Fill
Checklist:
- LL-106-N Shows ~0%.
- The level probe readout in the magnet power supply rack (cryoplatform) is ON, and the output from it to the PLC is ENABLE.
- PT-106-N is below 25 psig.
- PT-110-N reads a value between 20psig-60psig.
- Ensure EV-200-N is closed. It may have been left open earlier since the purifier was filled.
- Ensure VNFA on the purifier overview LN2 is CLOSED.
- LN2 tank (Tank #54) outside has > 20 inwc level.
- HCV13 is CRACKED OPEN.
Steps:
- Open EV-102-N
- Open EV-105-N to 100% (input 100% + press 'Enter').
- Open EV-100-N
- Monitor TE-104-N, TE-107-N, TE-108-N, and they should reach < 90 Kelvin.
- When the temperatures reach below 90 Kelvin, then Close EV-102-N.
- Monitor PT-106-N and ensure it doesn't reach above 25psig. If it reaches 25psig, then STOP the filling by Closing EV-100-N and Opening EV-102-N, then Close EV-105-N (input 0% + press 'Enter').
- Monitor LL-106-N reaching 90%.
- Close EV-100-N
- Open EV-102-N
- Close EV-105-N (input 0% + press 'Enter').
- After ~4 hrs, ensure TE-104-N, TE-107-N, TE-108-N are at room temperature and then Close EV-102-N.