1. Coil working group video-meeting P. Ferracin, J. C. Perez, S. Izquierdo Bermudez, X. Sarasola February 4th, 2014

2. Agenda Winding test updates Nb 3 Sn-Nb-Ti splice: procedure and fixture Single vs. double NbTi leads Wire for instrumentation 29/01/2014 P. Ferracin2

3. 29/01/2014 P. Ferracin3

4. Splicing and tinning tooling Feb 04, 2014 J.C. Perez4 The same tooling will be used for tinning and splicing using MOB 39 as flux and solder 96/4 Tin/Silver

5. Sequence of operations Feb 04, 2014 J.C. Perez5 CuttingTinning Tool assembly Clamping Courtesy of Nicolas Peray

6. Splicing configuration Feb 04, 2014 J.C. Perez6

7. Mid-plane shims Feb 04, 2014 J.C. Perez7

8. Flux and soldering alloy used at CERN Main issue: presence of an oxide layer after reaction. How to remove this oxide layer? – Activated fluxes: Improve solderability ×But the residue left can lead to corrosion ×Essentially banned at CERN – In SMC and RMC the splicing region is cleaned with a soft stainless steel brush MOB 39 offers the best results of the non-activated fluxes tried at CERN. http://en.mbosolder.com/products,solder-gel.phphttp://en.mbosolder.com/products,solder-gel.php Preferred soldering alloy: Sn 96.5% Ag 3.5%, T m = 221 o C Sn96.5Ag3.5 + MOB 39 is used for: – Pretinning the NbTi and Nb3Sn cables – The actual Nb 3 Sn/NbTi splice Feb 04, 2014 J.C. Perez8

9. Instrumentation & Quench heaters wires Feb 04, 2014 J.C. Perez9 Instrumentation wires: AXON reference HH2619 LH Conductor diameter 0.504 mm (0.15 mm 2 ) Conductor composition: Copper silver plated External wire diameter: 0.95 mm Wire insulation: polyimide tape wrapped (glued with a thin layer of fluoopolymer) Nominal voltage : 1000V AC Axon voltage test: (2*U N )+1000V= 3 kV Approx. price: 2220 €/km Quench heaters wires: AXON reference H 1619 L Conductor diameter 1.5 mm (1.34 mm 2 ) Conductor composition: Copper silver plated External wire diameter: 1.8 mm Wire insulation: polyimide tape wrapped (glued with a thin layer of fluoropolymer) Nominal voltage : 600V AC Axon voltage test: (2*U N )+1000V= 2.2 kV Approx. price: 4500 €/km

10. Updated status and possible plan 1.28/10-01/11, fabricate short plastic poles (BEND poles), 1 set 2.28/10-01/11, Wind/cure outer layer short Cu coil 3.28/10-01/11, Update BEND inner/outer layer spacers after short winding test 4.18-22/11, Update ROXIE/CAD inner/outer layer spacers 5.18-29/11, Fabrication inner/outer layer BEND/ROXIE plastic spacers (v3) for FNAL 6.02-06/12, Insulation of CERN Cu cable 7.9-13/12, Fabrication inner/outer layer ROXIE plastic spacers (v3) for CERN 8.06/01-17/01, Fabrication inner/outer layer ROXIE/BEND plastic spacers (v3) for LARP 9.06-31/01, LARP to wind 1st short coils (ROXIE LE/BEND RE) with plastic parts 10.13-31/01, CERN to wind 1 short coils (ROXIE) with plastic parts 11.10-14/02, Update ROXIE (v4) 12.03-14/02, LARP to wind 1sd short coils (ROXIE RE/BEND LE) with plastic parts 13.17-21/02, Update BEND (v4) and decision 14.16-19/12, Delivery 6 poles to FNAL 15.27-31/01, Delivery of 2 sets metal spacers (arrival 07/02/14) for CERN and FNAL 16.03-07/02, Launch procurement 1 set of metal spacers for FNAL 17.17-21/02, Launch procurement 5 sets of metal spacers for FNAL/CERN (market survey completed) 18.03-07/02, Launch the price inquiry for 3 sets of CERN poles 19.17-21/02, arrival of 2 sets of Cu wedges 29/01/2014 P. Ferracin10

11. CERN W&C tooling status All delivered and cleaned Next week assembly 29/01/2014 P. Ferracin11

12. CERN tooling status R&I tooling – Parts ordered Step files requested Nb-Ti lead related parts on hold – Expected in late March (1 reaction set) – end of April (the rest) CERN wedges – Expected by mid-March Work in progress to meet tolerances requirements 29/01/2014 P. Ferracin12

13. Susana Izquierdo Bermudez Field in Nb3Sn-Ti splice region 13 Magnetic Yoke & Pad =975 mm Non magnetic Pad =350 mm Non magnetic Pad = 225 mm

14. Susana Izquierdo Bermudez Field at the ends decay very quickly The fringe field of the magnet is negligible compared with the self-field of the interconnection 14 Field in Nb3Sn-Ti splice region Problems can be decoupled  Field in the interconnection can be computed analytically and/or with a very simple model I (kA)B p (T) (ANSYS*) B p (T) (ROXIE**) 17.311.3 211.21.6 “Recycling” a very simple model I did for the LHC main interconnections * Does not consider iron and the rest of the leads ** Does not account for current flow in between cables Design Parameter for Nb-Ti lead: B p = 2T Current distribution

15. Nb-Ti leads parameters (from Luc) Strand: 1.065 mm LHC strand, 1.6 Cu/SC ratio Cable: 34 strands, width of 18.15 mm and a mid-thickness of 1.92 mm. Field – In the nominal conditions (17.5 kA) we expect a field in the splice area of ~1.5 T – In the short sample condition (21.2 kA) we can say that the field in the splice area the field is ~2 T Critical current – Luc estimated approximately what would be the critical current of the cable 17 kA at 10 T and 1.9 K as high as 60 kA at 2 T and 1.9 K (to be confirmed) 44 kA at 2 T and 4.2 K 39 kA at 3 T and 4.2 K 19/12/2013 P. Ferracin15

16. Comparison End Spacer Heat treatment

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