1. RELICS INTEGRATION Many contributors Cryo amp vacuum vessel
Vacuum reminder
2K cooling of vacuum vessel
Loading cold bore end flange (~30kg)
Cold bore aperture restriction for cavity installation
Expert meeting
What distance to insert to be at full field?
To do for installation
Schedule
Cavity insertion system
Designed and built by CAPP team Lino /Harry/Frank

2. RELICS INTEGRATION Many contributors Cryo amp vacuum vessel Vacuum
Benoit (EN-MME)
Torsten, Johan, Dario (CRYOLAB)
Antonis
Jean-Michel
Main workshops
Wolfgang & Theodoros MD
Cryo amp vacuum vessel
ANSYS tested for strength vacuum one side or other
Complex piece with Copper and Stainless steel (brazing and electron beam welding)
Problems with one of two vessels found by J-M (luckily Lino agreed to make 2). Main workshop will try to repair other vessel
Vacuum
Reminder, no pipework at MRB end
2K cooling of vacuum vessel
Thermal studies by Dario Santandrea (thermal bridge and Antonis (cable heat input)
Test of 2K pipe for use in 2017?
2K pipe not used in 2016 but will be equipped with a heater/temp probe to test if SF liquid fills pipe at all times.
Thermal clamping of warm cables
Loading cold bore end flange (~30kg)
Concern for many months
Delayed ANSYS calculations – waiting for detailed drawing of welds by B Riffaud
Antonio (CERN) , Antonis (PATRAS)
Cold bore aperture restriction for cavity installation
Expert meeting
What distance to insert to be at full field?
To do for installation
Check that vacuum vessel fits on V2 (J-M & Herve)
Check thermal bridge fits
Schedule
Cavity insertion system Lino /Harry/Frank

3. RELICS INTEGRATION Many contributors Benoit (EN-MME)
Torsten, Johan, Dario (CRYOLAB)
Lino
Antonis
Jean-Michel
Main workshops
Wolfgang & Theodoros MD

4. Vacuum vessel
Designed by Benoit Riffaud EN-MME for equipping both cold bores.
He convinced his management that the CAST-CAPP project should be supported in spite of many ‘higher priority’ jobs
He has made many other drawings (thermal bridges, go – no go gauge etc) somehow fitting it in amongst his many responsibilities.
He has also made the follow-up with the main workshop, achieving a very fast turn around in fabrication and making modifications where necessary
He has ordered all brass bolts and flexible copper connectors for bridge to be used on the vacuum vessel
Some small mistakes due to urgency and MD as 2nd signature on drawings
We have been very lucky

6. Vacuum vessel ANSYS tested to withstand vacuum inside or outside.
Complex piece of Oxygen Free Copper (OFE) and Stainless steel
OFE Cu for the thermal requirements
High conductivity at 2K
Stainless Steel for the CF flanges (only seal viable at 2K)
Involves brazing and electron beam welding
Problems
Several leaks found (thanks to Jean-Michel)
One vessel is leak tight, the other needs some quite drastic repairs
Luckily Lino agreed to make two!
Main workshops working to repair the faulty fabrication
Jean-Michel to Comment?

7. 3-D view of vacuum vessel

8. Protruding cylinder in CAST Model smaller than reality !
Existing Model
Reality
Modifications:
Copper plate thickness reduced
Special low head screws
Modifications:
Clamp around superfluid sheath redesigned

9. Stress analysis on the Vacuum vessel – vacuum forces
Conclusions and Recommendations
This report has described the structural response of the instrumentation box used in the CAST experiment subjected to vacuum pressure. The European Standard codes NF EN and NF EN have been used to assess the maximum allowed values of the nominal design stress for pressure parts and the weld stresses, respectively.
The numerical analysis did not show relevant stresses in the structure and the resistance of the welds has been demonstrated with large safety margins.

10. Vacuum system reminder

11. Old Helium-3 gas /vacuum system
Vac pumps
Vac pumps
2015 system
Old Helium-3 gas /vacuum system
300K
70K 2K 2K
~40K
70K thermal shield
70K thermal clamp
Connected thermally but no gas /vacuum connection

12. Old Helium-3 gas /vacuum system
Vac pumps
Vac pumps
2016 system
Old Helium-3 gas /vacuum system
300K
70K
Cooling bridge 2K 2K
2-3K
70K thermal shield
70K thermal clamp
Connected thermally but no gas /vacuum connection blank flange

13. Old Helium-3 gas /vacuum system
Vac pumps
Vac pumps
2017 system ?
Vacuum and He supply needed. Modifications required
Old Helium-3 gas /vacuum system
300K
70K 2K 2K ?
2K ??
70K thermal shield
70K thermal clamp
Connected thermally but no gas /vacuum connection blank flange
blank flange

14. Thermal simulations
Cryolab studied how to ensure vacuum vessel could be maintained at 2K
(Dario Santandrea supervised by Torsten Koettig)
Didn’t trust that the 2K MRB return pipe was always full of SF liquid He
Decided to clamp around the sheath of the cold bore
Not a very smooth surface and zone is very congested
Headache for Benoit.

16. Ideally connections should be welded where possible Bolted solution will however be used instead of welded (timescales)

17. V2 Cold bore will be used – problem with protruding cylinder - Model smaller than reality
Existing Model
Modifications:
Clamp around superfluid sheath redesigned & thinned down , force of clamping very important for thermal contact. Weaker clamp than the original design

18. 2K pipe at MFB end now fixed to ensure no contact with 70K shield
Sketch of thermal clamping scheme by Cryolab for signal and service cables (Note model not final vacuum vessel design) 2K
70K
Thermal shield will be lifted by an insulator where it compresses the MLI on top of the magnet (MRB & MFB)
2K pipe at MFB end now fixed to ensure no contact with 70K shield

19. 30kg loading of cold bore flange
A concern for many months
Delayed ANSYS calculations
- Waiting for detailed drawing of welds by B Riffaud
- Availability of CERN engineer
Finally :
Antonio (CERN) , Antonis (PATRAS)
Antonis will report in next presentation.
Antonio did study but then was absent from CERN until today
- His conclusions:

20. Antonio’s starting conditions and results
Cold bore only fixed at welds at each end of the magnet, no support inside
ANSYS - Only potential problem is here
Frederic Savary believes it is also welded here

21. Antonio’s results and conclusions

22. Main model assumptions
CAST Instrumentation ports have been evaluated against vaccum pressure and dead weight
For the sake of conservativeness material properties of SS304L have been evaluated at room temperature
Weld static structural assessment against Eurocode 3
Global and local collapse against ASME Sec. 8 Div. 2
Instrumentation weight modelled as masses
Material
Yield Strength
(MPa)
Ultimate Strength
SS 304L
225
490
Mesh detail

23. Results (I)
Results below indicate minimum acceptable thickness (as per Eurocode III) for critical lip weld
Prelimenary results from elastic analysis evinced relatively high stress regions around the lip weld for the nominal load
Stress from elastic rules

24. Results (II)
Re-examination of those stresses against more sophisiticated plastic failure criteria suggest that those stresses would be easily relieved upon local yielding
Results show ductility exhaustion ratio is below one for 1.5x the design load proving resistance against global and local collapse up until that load

25. Cold bore aperture restriction for cavity installation
Great difficulty finding information on cold bore
Contradictions between drawings 43mm (M Genet) and Surveyors report (42mm)
This magnet was measured by field probe operating inside an anti-cryostat.
Maximum diameter of anti-cryostat tube 39.9 mm
5 mm spacers at couplers every ~600 mm diameter /-0.1 mm
Anti cryostat is somewhat flexible due to couplers

26. Entrance restrictions? Ask Metrology to make measuremsnts4
No problems with entrance aperture
V1 beam line (Jura side)
Position 3
Max diameter = mm
Min diameter = mm
Position 2
Max diameter = 42.97mm
Min diameter = mm
Position 1
Max diameter = mm
Min diameter = mm
Position 4
External diameter = mm
V2 beam line (airport side)
Position 3
Max diameter = mm
Min diameter = mm
Position 2
Max diameter = mm
Min diameter = mm
Position 1
Max diameter = mm
Min diameter = mm
Position 4
External diameter = mm

28. Cold bore is ‘pinched’ by ‘noses’ of magnet plates In some magnets the clamping of the plates produced distortions in cold bore so that the anti-cryostat would not fit in !

29. Cold bore apertures

30. Go – No Go gauge tests Length Diameter V1 comments V2 (cm) +0.2/0.0 20
+0.2/0.0 20
40.0
OK all 10m
resistance 1.15 & 2.55m
40.5
STOP 37 cm
resistance 4.3 & 5.9m
41.0 40 50
STOP at 1.3m
STOP at 8.3m
STOP at 34 cm
STOP at 70 cm

31. EXPERT MEETING No show stoppers found
General agreement that a method to lessen the load on cold bore from the vacuum vessel would be advisable
Missed two magnet experts or their deputies A Siemko & L Bottura.
Thanks to L Walckiers and S Russenschuck for attending

32. What distance to insert CAVITY to be at full field ?

33. Data from 2002 CAST Collaboration Meeting
20 cm cavity

34. Integration – left to do

35. To do Further metrology of cold bore?
Support system to mount vacuum vessel
Jean-Michel designed with Herve Martinati (PH-DT FSU), some mods needed.
Should be tested again today
Check vacuum vessel fits
Check thermal bridge fits
Trial insertion of spare cavity
Make a new warm cryostat end plate flange
Need at latest in 3 weeks

36. Schedule

38. Cold bore exit mechanics – Thanks to Frederic Savary