sPHENIX discussion of the superconducting solenoid

[Kin Yip <kinyip AT bnl.gov>]

Hi John et. al.,

Thanks for your comment. 

> I think the drawings say the inner wall is 10 mm 5083 aluminum,

I've been just looking at this.   Looking for information over those Italian drawings is never easy.
I think I can find it in the following way in our \\bnl.gov\c-adnas\babar disk server from this PDF file :

"Volume 6 AS BUILT DRAWINGS/6.1 GENERAL AND CRYOSTAT.pdf".

 Page 9, 620RM07241, it tells us that item 4, "VIROLA INTERNA"  (Internal Shell Ring) --- Al 5083 --- is in the drawing of
620RM07246 which can be found on p.11.   Near the bottom on p.11, it seems to indicate that the thickness of the Al shell has a thickness
of 10 mm.

Similarly, the external shell ring which one can find on p.10 (620RM07245), the thickness there is 25 mm.

Kin

PS:  Steve Bellavia taught me how to calculate the maximum stress allowed = Moment *C / Inertia,

where Moment = weight * Length of the cryostat / 2 ---- (as the biggest moment is in the center),
          C = radius
          Inertia = pi*radius^3 * thickness

=> Maximum weight allowed  =  2*maximum_stress*pi*radius^2 * thickness/Length

thickness = 0.01 m (=10 mm)
radius = 2.84 m/2 = 1.42 m
Length = 3.849 m

Maximum stress for 5083 (Al) = 40 ksi ... Let's be conservative and give a safety factor of 3
                                              => maximum_stress ~ 40/3 ksi ~ 9.19E7 Pascal

=> maximum weight allowed ~ 3.03E6 Newton  or  a mass of 3.09E5 kg  (or 300 metric tons) !

If this is correct, we don't need to worry about it :-)     But I doubt that it's true :-)

On 07/10/2017 03:19 PM, John Haggerty wrote:

Kin,

I don't know for sure; I think the drawings say the inner wall is 10 mm 5083 aluminum, but at SLAC they lifted the solenoid with a spider that fit inside the cryostat like this:

http://www-project.slac.stanford.edu/slacpix/BaBar/16_mag/to_290.jpg

so I always assumed that it wasn't a problem if a couple of people threw their weight around.

sPHENIX itself does not intend to put any load on the cryostat inner wall as far as I know.

On 7/10/17 1:28 PM, Yip, Kin wrote:

Dear Mike, Paul, Jon & Dave,

As Paul Orfin asked below, I sometimes wonder about this too when I saw people walk through the solenoid.

Can we safely walk and stand inside the inner solenoid ?  Approximately how much weight can the inner solenoid handle ?

/Sent from my Verizon LG Smartphone/

------ Original message------
*From: *Orfin, Paul
*Date: *Mon, Jul 10, 2017 12:37
*To: *Yip, Kin;
*Cc: *
*Subject:*RE: Sonny and Joe have taken the half-rack ... waiting for the survey result ... carpenter putting up the railing

Kin,

Has anyone determined the maximum load allowed  on the inner diameter of the solenoid?  I don’t know the details of the inner plate thickness but there may be a weight limit for materials being brought in by foot.  I just want to make sure there is no damage to the solenoid.  I understand that the magnet was built to handle large magnetic forces but concentrated loads from someone’s foot for instance, may not have been taken into design consideration.  Looking at the pictures of people in the magnet made me think of this just now.

Thank you,

Paul Orfin
Cryogenic Systems, Collider-Accelerator Department
Brookhaven National Laboratory
Telephone: (631) 344-2899

*From:*sPHENIX-magnet-l [mailto:sphenix-magnet-l-bounces AT lists.bnl.gov] *On Behalf Of *Yip, Kin
*Sent:* Monday, July 10, 2017 11:50 AM
*To:* sphenix-magnet-l AT lists.bnl.gov
*Subject:* [Sphenix-magnet-l] Sonny and Joe have taken the half-rack ... waiting for the survey result ... carpenter putting up the railing

Hi,

45 minutes ago or so, I showed Sonny Simaiuta and Joe Dambra where the half-rack was in Bldg. 912.  They have taken it to Superconducting Magnet

Division to make small modification.

I’ve just taken another picture this morning around the Magnet/steel box :

https://collab.external.bnl.gov/sites/sPHENIX-Magnet/Pictures/High%20Field%20Test/Return%20Yoke%20Construction/2017-7-10.jpg

Apparently, the survey was taken late last Friday after the magnet was slightly rotated.  Now, we’re waiting for the survey group to analyze

the data.  Matt (who has been doing the analysis)  is out today and Frank Karl is trying to see whether he can do the analysis   or   they have to wait

for Matt to come back tomorrow.

Richard Meier was moving his cables.   I also saw that a carpenter was installing the railing for the platform (all in Aluminium) in the Lead-End.

So, the schedule  that D. Phillips sent last Friday (below) seems to be materializing (though Dave is not here today).  Hopefully, the riggers and Ray Ceruti’s group can install the Extension this Wed.

Kin

*From:* Phillips, David B
*Sent:* Friday, July 07, 2017 11:45 AM
*To:* Ceruti, Raymond B <rayc AT bnl.gov <mailto:rayc AT bnl.gov>>; Yip, Kin <kinyip AT bnl.gov <mailto:kinyip AT bnl.gov>>; Mills, James A <mills AT bnl.gov <mailto:mills AT bnl.gov>>; Hock, Jonathan <jhock AT bnl.gov <mailto:jhock AT bnl.gov>>; Streckenbach, Brian <bstreckenbach AT bnl.gov <mailto:bstreckenbach AT bnl.gov>>
*Cc:* Kobasiuk, Frederick D <kobasiuk AT bnl.gov <mailto:kobasiuk AT bnl.gov>>; Folz, Charles <cfolz AT bnl.gov <mailto:cfolz AT bnl.gov>>; Anerella, Michael D <mda AT bnl.gov <mailto:mda AT bnl.gov>>; Karl, Francis X <karl AT bnl.gov <mailto:karl AT bnl.gov>>; Ilardo, Matthew <milardo AT bnl.gov <mailto:milardo AT bnl.gov>>
*Subject:* sPHENIX Magnet plan for next week

sPHENIX Magnet plan for next week:

Friday 7/7 – Riggers place cryostat in correct position

Friday 7/7-Monday 7/10 – Survey confirms cryostat is correctly positioned

Monday 7/10-Tuesday 7/11 – Carpenters install handrails and access ladder to internal Lead End platform.

Wednesday 7/12 – Riggers and Magnet Division install Valve Box Extension

Monday 7/10 - until completed – Drilling/taping holes in return steel

Thursday 7/13 – until completed  - Riggers install return steel (this needs to be coordinated with MD Teck’s working on Dog House connections)

Week of 7/17:

-MD Teck’s continue with Dog House connections

-Riggers install Return Steel and shield blocks for Valve Box Platform

-Carpenters assemble scaffolding for access to External Dog House

-Carpenters install handrails etc for Valve Box Platform

David Phillips

Building 911B

Upton, NY 11973

631-344-4671, Fax 631-344-5954, Cell 631-804-9477

On site pager 344-3456 then 4267 then your number



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