sPHENIX discussion of the superconducting solenoid

["Yip, Kin" <kinyip AT bnl.gov>]

Hi,

 

This evening around 5 pm, I saw Roberto and Brian van Kuik chatting next to the Liquid Nitrogen tank for the sPHENIX Magnet (in 912).  Checking with them, I understand that the flow controllers have been installed and since then, the air has been got rid of and purged.   When I arrived, they’ve just started

filling in the Liquid Nitrogen tank used for the LN2 cool-down.    Eventually, the tank level was set at 57% (somewhat arbitrarily).

 

I attach the HMI picture and you can see that the tank (in the middle of the picture, slightly to the right) is at 57% now.  [  Apparently, in the pipelines in the picture, I believe that “yellow” seems to be helium and “green” seems to be nitrogen. ]

 

Roberto told me that he can start circulating the helium, ie., cool-down, any time now, as soon as he takes care of his daughter, eat / sleep …

and train his crew in the Cryo group to watch the cool-down.   I’m wondering if sending an email to Roberto every hour or so will speed

up or slow down the process J

 

Kin

 

PS:

I was asked “what positioners”.   Positioners that I’ve mentioned are the devices used to control

opening/closing the valve and read back how much the valve is opened/closed.  For the low-field test,

(since the existing positioners were burnt due to short circuit), the Cryo group is using some “cheaper

positioiners” which can open/close the valves in different degrees but they don’t provide readback.

 

 

From: Kin Yip [mailto:kinyip AT bnl.gov]
Sent: Wednesday, February 24, 2016 2:40 PM
To: sphenix-magnet-l AT lists.bnl.gov
Subject: Brief Summary of sPHENIX Magnet Biweekly meeting (Feb. 24, 2016)

 

We've had the shortest meeting ever : essentially we finished our meeting at 1:45 pm today.

1. Roberto told us (and I actually just went to Bldg. 912 and saw) that Rich Meier/L. Masi Jr. are NOW replacing the two BaBar/SLAC
   flow controllers with the flow controllers that BNL has always used and we're familiar with.   Once the new flow controllers are
   physically installed in the piping, Roberto can get rid of air, and then pump and purge.   He'll then start cooling-down tomorrow (Feb. 25).  
   The electrical wiring and power supply (which we're ordered and should come overnight) for the flow controllers can be finished during cool-down.
  
   The shield flow controller needs to be verified also for operation.  But these are the BNL flow controllers, not SLAC ones.

2.  Achim Franz is testing (as I write this) his magnetic field testing probes ... He's still not heard from D. Phillips where his data acquistion tray/table
    can be placed.  He'll go to find Dave to figure it out.    He just needs two 110 V outlets.  Right now, he's just used the outlets close to the Magnet.

3.  Since the positioners have been burnt out, Roberto's buying 6 positioners (we need 5) using sPHENIX money (~$10K) which will be used for
    the high-field test and the future sPHENIX in Bldg. 1008.


{   I've placed 3 HMI screenshots  (the Cryo system overview for the Magnet) on the agenda/indico page :  https://indico.bnl.gov/conferenceDisplay.py?confId=1801. 
     Not very exciting yet ....  }

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