[Esr-users] ESR status and recovery of Halls

[Dave Kashy]

Hello All,
The attached file shows the current status of all of the magnets in the ESR complex.
It shows that we have not made significant progress in recovering from the trip two days ago.

It appears that shutting off Hall B completely was not enough to make the recovery simple.
Yesterday we prioritized Hall A first and Hall C second in our meeting after the 08:00 meeting at MCC.
Apparently this did not go so well.

Cryo started the transferline yesterday afternoon and we still have not made significant progress. 

This morning I met with the cryo group to discuss the possible causes.
1) we may additional loads - So each Hall A and C as well as cryo should check the VJ pressure or temperatures to look for additional heat loads.
2) We may have lost capacity of the ESR refrigerator so Cryo will check to see if flows and temperature ratios are normal
3) We may have magnets on the wrong type of return 
4) we may be trying to cool too much at the same time


We decided that we must start to make progress and we will follow the priority guidance that was agreed to yesterday.

Recover A, then recover C then recover B

As such:

1) Hall C should prioritize their system to take only 5 g/s until all Hall A magnets are full and stable
2) Cryo and Hall A should put all magnets on warm return and cool only a few at a time until those can be put on cold return while giving those on warm return just enough to keep them from warming significantly.
3) Hall B will wait until all other magnets are on cold return. 
4) After all the Halls are recovered, the 10,000 liter dewar at ESR will be topped off.


If Hall C needs more or can take less flow please let me know.

Thanks
Dave Kashy
 
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