sPHENIX discussion of the superconducting solenoid

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

Agenda and powerpoint : https://indico.bnl.gov/conferenceDisplay.py?confId=2982

 

 

1.       D. Phillips has discussed with a technician (not electrician as somebody has suspected !) to use a limiting switch system to prevent the cab of the crane from hitting the Valvebox (when it’s installed at the top).  They have used that system before and they’ve just tested it and it worked.  They just need to install that “limiting switch” at the appropriate place --- they just held the limiting switch by hand during the test.

2.      R. Ceruti and his team have nearly finished (~98%) the Extension assembly by the end of this week.  Below are the photos he’s shown us

and we can see that the superconducting bus are contained inside Aluminium heat shield and the 30 layer MLI are in between:
https://collab.external.bnl.gov/sites/sPHENIX-Magnet/Pictures/Cryo%20Extension/2017-3-28.zip

https://collab.external.bnl.gov/sites/sPHENIX-Magnet/Pictures/Cryo%20Extension/2017-3-29.zip

IMG_20170329_091658635_HDR.jpg (in “2017-3-29.zip”) shows the 30 layer MLI.  They are buying a flex connector (which may be a couple weeks’ wait) to connect all the plumbing system.

3.      J. Hock has showed his progress in flame cutting, tapping/drilling and assembling in % after working through his detailed MS Project software.
We have a baseline to compare with in the future biweekly meetings.

Streck delivered the 3 pieces of roof steel (this Mon./Tue.) that they’ve machined for us.   Pictures may be seen in my powerpoint in the indico page as well as https://collab.external.bnl.gov/sites/sPHENIX-Magnet/Pictures/High%20Field%20Test/2017-3-28%20Streck's%20Devliery.zip .

4.      Under the radar, I informed people that we (including R. Than, C. Schultheiss, A. Franz, M. Annerella and myself) have worked on the MS Project for the sPHENIX CD1 review.  Jim has sent us comments/corrections/checks more than one time and we’ve responded quickly to correct/improve on the project file.  We’re also starting to see how much we need to modify the magnet portion of the Conceptual Design Report for CD1.  The Cryogenic portion needs to be modified quite a bit because we had put in a version which would have a separate plant, but now we’ve decided to attach to the RHIC Cryo system.

 

5.      Most of the time of the meeting, we have discussed about cabling and connectors.  Since P. Giannotti is busy with his documentation work, Tom Tallerico kind of took over and will organize the cabling and connectors. 

 

From Paul Giannotti’s presentation: https://indico.bnl.gov/getFile.py/access?sessionId=0&resId=2&materialId=1&confId=2803, at page 2, we can see that there are 12 connectors for Cryo connections and strain gauges, excluding the voltage taps.  Tom Tallerico will try to show us the cabling and connections in the next meeting.

During the meeting, Tom showed us the webpage of a British company: http://www.cmr-direct.com/en/rectangular-connectors .   Tom was wondering whether it’s worth spending ~$110-120 to buy a “cryogenic” D connector as other cheaper ones would do.  We discussed for a while as the old non-cryogenic ones (from BaBar) still work which we will still use.   But at the end, D. Phillips advocated strongly that we shouldn’t try to save a little money and should buy the good cryogenic D-connector.  Ed. O’Brien has agreed (who is the person who is approve the purchase).  Tom’ll consult with Carl and Piyush to find the best candidate for cryogenic D-connector.

After the meeting, Tom and I went to find Sonny.  Tom just wrote the following in a private email and I just included it here:

“Sonny will be running his own 12 conductor cable (including spares) through the 2 -3/16 pipe. The maximum diameter is approx. .25 inches. He is supplying his own cables and connectors. He will use the shared pipe volume and he is taking care of that end of the cable run completely. I do not have to worry about the voltage tap end of the job.  He showed me the actual extension.”

We’ve also discussed about how to put the cables through the Extension hole (which has 2.5” OD and 2-3/16 ID as Tom said above) under the superconducting bus.  D. Phillips did some calculations and concluded that this hole should be enough to hold all the 12 cables.  Sonny’s voltage tap cable is another just 0.25”.  It’s been suggest that we can at least connect one end of the cables in 902 (SMD) before installing the Cryo Extension in Bldg. 912.

 

6.       A few miscellaneous item that I’ve learnt during and before the meeting :

--- All 12 brackets/jack-supports in Florida State University are being picked today and hopefully will be shipped to us in a couple days.

--- It’s anticipated that we’ll never detach the Cryo Extension from the two doghouses that it’s now attached to, during the transportation
     to 1008 (even if the extension is not transported together with the Magnet Cryostat).   The upper end of the doghouses will be disconnected     
     from the ValveBox.

--- Sonny/Piyush told me before the meeting that: due to the introduction of the Cryo Extension and its new superconductor, the existing voltage taps (VT04 and VT12) on page 18 of C. Schultheiss’s presentation ( https://collab.external.bnl.gov/sites/sPHENIX-Magnet/Past%20Presentations/2017-3-15%20sPHENIX%20Quench%20Detector%20Review.pptx )  will be moved upwards so that with another pair of voltage taps, we can monitor the voltage across the entire joint.