[Esr-users] update: ESR status and recovery of Halls

[Joe D. Wilson, Jr]

Hello,
Update as of 1650 on 7Mar18: Except for Right Dipole, all Hall A magnet have
liquid and on cold return. The overnight plan is to leave the Hall A Right
Dipole on warm return to continue cooling while the ESR dewar refills. The
expectation for the morning of 8Mar18 morning is reach ESR- Hall A
conditions such that more ESR capacity can be shifted to Hall C. 
Thanks!

-----------------
Joe D. Wilson, Jr.
Cryogenic Operations Engineer

Jefferson Lab
www.jlab.org
757-269-7722
jwilson at jlab.org



-----Original Message-----
From: Esr-users [mailto:esr-users-bounces at jlab.org] On Behalf Of JLab
Sent: Wednesday, March 7, 2018 4:47 PM
To: esr-users <esr-users at jlab.org>
Cc: Patrizia Rossi <rossi at jlab.org>; Rolf Ent <ent at jlab.org>
Subject: Re: [Esr-users] ESR status and recovery of Halls

Hi,

Dave Kashy and I just had a chat. I understand that Halls B and C are empty
(mostly) while Hall A is trying to fill their magnets without much success -
I think I saw LQ3 been put on cold return recently.  If the above statement
is correct, could this this be due to a problem (or problems) like
insulating vacuum (I think that I saw a question from Dave to the esr-users
list asking about this but never saw an answer) or something else?

Thanks in advance for any help you guys can give me to understand what is
going on - Javier

  
> On Mar 7, 2018, at 10:41 AM, Dave Kashy <kashy at jlab.org> wrote:
> 
> 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
> <Status of Halls 3_7_2018 10
am.pdf>_______________________________________________
> Esr-users mailing list
> Esr-users at jlab.org
> https://mailman.jlab.org/mailman/listinfo/esr-users


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