sPHENIX discussion of the superconducting solenoid

[Kin Yip <kinyip AT bnl.gov>]

Hi,

Let me reply to the entire mailing list so that people may point out if I say something wrong.

The linear pots. are in longitudinal directions (axial) and I heard from Ray Ceruti that pots. 1 and 2 are at one end and pots. 3 and 4 are the
other end correspondingly.  { I can check next time when I go there. }    

The linear pots. are attached to some bellows (steel ?) which in term are attached to the coils.   The linear pots. are outside the vacuum, exposed to air and so
they won't be too cold at the end.  

The Al stabilizer composition is of great interest recently.     The following are two certification information (found by Pasquale) :

https://collab.external.bnl.gov/sites/sPHENIX-Magnet/Shared%20Documents/Documents%20introduced%20or%20sent%20to%20us%20by%20Pasquale%20Fabbricatore/2016-2-9%20BABAR%20-%20EUROPA%20METALLI%20Tests.pdf

https://collab.external.bnl.gov/sites/sPHENIX-Magnet/Shared%20Documents/Documents%20introduced%20or%20sent%20to%20us%20by%20Pasquale%20Fabbricatore/2016-2-9%20BABAR%20-%20EUROPA%20METALLI%20Al%20certification.pdf

There is an old article about its properties for various purity of Al (from the Dzero expt.) :
https://collab.external.bnl.gov/sites/sPHENIX-Magnet/Shared%20Documents/Documents%20introduced%20or%20sent%20to%20us%20by%20Pasquale%20Fabbricatore/Pure%20Al%20D0.pdf

They are mentioned in various Babar paper such as : 
https://collab.external.bnl.gov/sites/sPHENIX-Magnet/Shared%20Documents/BaBar%20Documents/IEEE%20TRANSACTIONS%20ON%20APPLIED%20SUPERCONDUCTIVITY,%20VOL.%209,%20NO.%202,%20JUNE%201999.pdf

They are also mentioned in "BaBar Note 233.pdf"  (which can be found in our BaBar server).

Also, pages 33-34 of
Volume 5 DESIGN AND QUALITY CONTROL REPORT/5.1 GENERAL AND MAIN COMPONENTS\Volume 5.1 Design and Quality Control Report GENERAL MAIN COMPONENTS.pdf

in our BaBar server  also mentions this.
 
In fact, Jim sends you some of the above stuff on Feb. 12, 2016.

Kin

On 02/26/2016 10:24 AM, Sondheim, Walter E wrote:

Hi Kin, trying to understand the linear potentiometer data where the shrinkage corresponds to .030 inches – is this in the radial or longitudinal directions or both, is this half of the shrinkage – each potentiometer has changed by .030 inches? Are these units measuring the delta between the outside of the cryovessel (vacuum) and the coil package? What is the aluminum alloy in the coil package can?

Sorry for all these questions  - I guess you too have looked to see if this delta corresponds to a 17 degree change –

Cheers,

Walter

 

From: sphenix-magnet-l-bounces AT lists.bnl.gov [mailto:sphenix-magnet-l-bounces AT lists.bnl.gov] On Behalf Of Yip, Kin
Sent: Friday, February 26, 2016 8:02 AM
To: sphenix-magnet-l AT lists.bnl.gov
Subject: [Sphenix-magnet-l] Pots/strains vary as the temperature decreases ...

 

Hello,

 

“2016-2-26 08-14.jpg” was taken at 8:14 am (about 24 hours after the start of cool-down).   The outlet temperature is probably the one

to watch and it has been reduced by only ~16 K after 24 hours.   I had a plot for the temperature in the screenshot and the temperature

reduction may accelerate ?!

 

Half an hour ago or so, I went down to the sPHENIX Magnet to see whether the magnet has shrunk.  Paul Orfin seems working on some leak

control in the pipelines (in the area outside the magnet/valvebox) …

 

The linear potentiometers have been calibrated such that we got “inches” (as Piyush explained below).   I took a copy at 9:09 am.  They seem

to have shrunk by more than 0.03 inches to almost 0.04 inches.  ( lin_pot.jpg )

 

I also grab a few strain measurements and plot … (strain.jpg )

 

Kin

 

From: Joshi, Piyush
Sent: Thursday, February 25, 2016 4:35 PM
To: Yip, Kin <kinyip AT bnl.gov>; Giannotti, Paul <gia AT bnl.gov>
Cc: O'Brien, Edward <eobrien AT bnl.gov>; Lynch, Don <dlynch AT bnl.gov>; Dimaiuta, Sebastian A <sonny AT bnl.gov>
Subject: RE: Conversion from resistance to strain for Lin. Pot.

 

Hi all,

Four pots are being read every 15min on slow logger. Right now they are reading around 0.207 or so. at the end of cool down if that number reads, say, 0.257 then coil has moved by 50/1000 of an inch.

Piyush