sPHENIX discussion of the superconducting solenoid

[Kin Yip <kinyip AT bnl.gov>]

Agenda/powerpoints : https://indico.bnl.gov/conferenceDisplay.py?confId=2598


1.  I first discussed the change of the roof of the return yoke for the Full Field Test as the Health Physicist have found the thicker steel to be
contaminated with Co-60 (in their re-analysis) so that we couldn't ship it out to the company Streck for machining.  Luckily, J. Hock can find
some other steels to replace the original steel but now the roof is flat.

After getting help from N. Tsoupas to change the roof of Wuzheng's original (preprocessor) model (by changing the material from "IRON10"
to "AIR"),  I ran the Opera analysis and found that there is little change in the magnetic field.  For example, the central changes only by 0.2 G
in 1.37 T and I also showed the leakage magnetic field above the roof, the max. magnetic field change slightly more than 1 G (< 2 G).

I also showed that B. Parker did an independent Opera analysis (in which his model was constructed from J. Cozzolino's engineering file) and
confirmed my results.

This presentation can be found in the above-mentioned indico link as well as here :
https://collab.external.bnl.gov/sites/sPHENIX-Magnet/Past%20Presentations/2016-11-23%20Flat%20roof.pptx


2.  J. Cozzolino has presented his newest ANSYS structural analysis of sPHENIX Magnet at full current (4596 A) --- version J (now).   In the
presentation, he showed the magnetic field distributions, lorentz force densities in coil and iron, total deflection, stress in the support jack, side
wall and cryostat wall.  In general, his conclusion is: "stresses and deflections appear to be quite manageable".    There is a corner in the support
jack where we saw a max. of ~11 kpsi.   This may be a concern if we use Al instead of steel (John has assumed stainless steel in his analysis) but
could be just a modelling issue of sharp corner.    He said that he can revisit if we really use Al.

This presentation can be found in the above-mentioned indico link as well as here :
https://collab.external.bnl.gov/sites/sPHENIX-Magnet/Past%20Presentations/2016-11-23%20sPHENIX%20FE%20Analysis-J.pptx


3.  We then discussed a little about the return yoke construction.  For the roof steel, J. Hock needs to get the new steels to be re-checked by the HP
(and he needs rigger/technicians to help before HP can check) and then he'll re-submit the PO to Streck again, to be machined over there.

J. Hock and D. Phillips were not in the meeting.  M. Anerella said that they have drilled whatever need to be drilled now.   But J. Hock/D. Phillips may
have more later ... The work progressed slowly because the lack of availability of riggers, technicians or welders at the same time.  There may be
gap in time between the time when riggers finished the work and when the technicians could start etc.

The broken drill was to be repaired in Connecticut according to what I've heard from J. Hock.  We're using the other one (also from PHENIX). 

3.1  As Ed O'Brien told us, now they're asking the prices from the Central Shop for making the Jack Support in welded steel (materials and labor)
and  Florida State University (FSU) for the same Jack Support but in bolted aluminium (material only ... as labor is "free").    FSU apparently
can't work with steel in this task.


4.  M. Anerella and H. Hocker told us that they've asked R. Ceruti's guys to pick up the components from the Central Shop (though they're not
sure whether it's done).   After the meeting, Paul Giannotti and I went downstairs and found R. Ceruti and he told us indeed that they had
already gotten the completed components from the Central Shop and even showed us all (the two junction-boxes, busses etc. etc.)   

I talked with M. Anerella "privately" after the meeting and he expected that the assembly may start in Dec. and will be completed by the end of Dec.
or early Jan.

I've just reminded people again and again that we need P. Giannotti and Sonny A. (and probably C. Schultheiss) to point out/mark down where the
new voltage taps will be so that they will be made.   Everybody is assuring me that this is the last and least thing to worry about :-)


5.  W. Pekrul reported that he's setup the development front-end-controller with new ADC boards and now making cables to wire external clock and trigger.
Apart from that, I understand that people are busy with the RHIC/AGS start and will hopefully get back to work on sPHENIX Magnet project after
Thanksgiving !


6.   A. Franz relayed J. Haggerty's news that he's bought the new probes.  Originally, we hoped a new postdoc would pick up the magnetic field measurement
task but now J. Haggerty has volunteered for this job :-)


7.  I talked about the issue how long the Cryo group needs after the platform and Valve Box are ready for them.   P. Orfin and others all think and hope that
most old connections are still there and we just need to reconnect them to the Valve Box again.  ( Hopefully, one month should be enough. )

Asked by D. Lynch, we then went on to discuss what P. Giannotti and P. Orfin have found in their visit in 1008, with the original intention to see how/where the connection
tie-in should be.   But Don's questions quickly made P. Orfin conclude that they may need to re-visit there again.  P. Orfin will show us some pictures / drawings / schematics
in the next meeting so that we may understand what the PHENIX guys (D. Lynch, E. O'Brien, P. Giannotti) were talking about during the meeting.  

When the new cryo pipes are installed, the radiation shielding blocks will need to be taken down and according to P. Orfin and P. Giannotti, this seems to be a tricky or
impossible task as there is a 45 deg. angle (and other things that I can't understand without seeing the picture).  But apparently, somebody has done it before and so
there should be a solution.   Hopefully, we can just put back the same shielding blocks as they are now so that we don't need to do radiation analysis !!

At the end, D. Lynch et. al. even discussed about the liquid nitrogen dewar currently at PHENIX and whether its location is good for the future sPHENIX or they should
move it to somewhere else.   No conclusion yet.