1st FNAL-CERN Collaboration Meeting Fermilab, May 13, 2011 Strand and Cable R&D D. Turrioni, Fermilab 1st FNAL-CERN Collaboration Meeting Fermilab, May 13, 2011

Outline Cable and Strand Specifications Cabling machine, tooling and instrumentation Cable study and development QA/QC Summary 13 May 2011, FNAL-CERN CM1 Strand and Cable

Cable Specification Parameter Value Cable Cross Section Un-reacted Reacted Cable unit length, m 210 Rectangular Keystoned Number of strands 40 Transposition angle, degree 15 Transposition direction Left-hand screw Mid-thickness, mm 1.269 1.307 Thin edge, mm 1.167 1.202 Thick edge, mm 1.370 1.411 Width, mm 14.70 14.847 Key-stone angle, degree 0.79 0.81 Insulation thickness, mm 0.150 0.100 The large aspect ratio of the cable and the present cabling procedure require the cable fabrication in two stages: the rectangular cable with narrower width and lower packing factor and the keystone cable with final parameters Long Unit Length ~ 210 m 13 May 2011, FNAL-CERN CM1 Strand and Cable

Strand Specification Nb3Sn RRP-108/127 strand produced by Oxford SC Technology Relatively Stable Strand@ 4.5 K and 1.9 K High Jc 13 May 2011, FNAL-CERN CM1 Strand and Cable

Cabling Machine Respooler Compact machine. Two major upgrades : Continuous cable pitch regulation with the electronic synchronization of the main wheel and the caterpillar motion 42-spool wheel Max Speed of 5 m/min Respooler 13 May 2011, FNAL-CERN CM1 Strand and Cable

Cable Forming Fixtures Turk head Keystoning Tooling Side Rollers and Mandrels 13 May 2011, FNAL-CERN CM1 Strand and Cable

Instrumentation Mitutoyo Digimatic Multiplexer MUX-10 Turk head Mitutoyo Dial Indicator ( 1 µm resolution ) Keystoning tooling Dial Indicator ( 1 µm resolution ) Mitutoyo Micrometer ( 1 µm resolution ) PC Measurements of the two dial indicators are acquired every 3 cm at 1 m/min of production speed. 13 May 2011, FNAL-CERN CM1 Strand and Cable

40 Strands cable for practice coil Cable Measurements 40 Strands cable for practice coil 13 May 2011, FNAL-CERN CM1 Strand and Cable

Cable development Design and parametric considerations were used in the development of the cables to be made of Nb3Sn RRP wires. For the cable geometry contemplated by the magnet designers the mandrel was designed in order to provide sufficient room for the strands to wind around it without excessive damage. This requirement, which accompanied the requisites for mechanical stability, allowed determining quite accurately the number of strands needed for each cable geometry. 13 May 2011, FNAL-CERN CM1 Strand and Cable

Cable Design Parameters The geometrical relationship between a cable of desired width wC, to be obtained with strands of diameter d, and the required mandrel width wm is shown in the first expression below where  is an empirical factor determined by experiment. The second expression is a simplified formula used for the purpose of parameterizing the number of strands needed for each cable geometry. N is the number of strands in the cable,  the cable lay (or pitch) angle A large body of data acquired during Nb3Sn conductor development shows that when cabling Nb3Sn RRP wires, it is important that:  ≥ 1 TD-10-022 “Nb3Sn Cable Development for the 11 T Dipole Program” 13 May 2011, FNAL-CERN CM1 Strand and Cable

40 Strands Cables List Next slides show results of: Cable Traveler Name Type Length, m Strand design No. strands Strand size, mm Mandrel width, mm Lay angle, degree PF, % SS Core R&DT_101007_40_1_0 R 50 Cu 40 0.697 13.93 15 83.4 N R&DT_101026_41_1_0 41 14.24 15.5 84.0 “ R&DT_101101_40_1_1a 13.95 83.8 Yb R&DT_101101_40_1_1b 17.5 85.1 R&DT_101109_40_1_0 10 RRP108 0.703 82.8 R&DT_101109_40_1_1 83.7 R&DT_110103_40_1_0 325 0.699 13.63 R&DT_110315_40_1_0 K 230 RRP114 13.92 86.3 Ka 85.8 R&DT_110420_40_1_0 190 a Rectangular cable has been annealed in Argon at 180 Cº for 1 hr b Stainless steel core used was 9.525 mm x 25 mm in size. Next slides show results of: Five Rectangular copper practice cables with and without core Two rectangular Nb3Sn practice cable with and without core (108/127 strand design) One Keystoned Nb3Sn practice cable without core (114/127 strand design) 13 May 2011, FNAL-CERN CM1 Strand and Cable

Cable development Rectangular Copper Cables The first forming step of the rectangular cables to be used to produce keystoned cables 14.7 mm (with 40 strands) and 15.1 mm (with 41 strands) wide was finalized out of hard Cu wires of 0.7 mm nominal diameter. The rectangular cables were 1% narrower than the final desired widths of the keystoned cables in order to account for the 1% width expansion to be expected when performing the second, keystoning, cabling step. Selected design was the 40 strand cable because of CERN cabling machine capability Cable Traveler Name Length, m No. strands Strand size, mm Mandrel width, mm Lay angle, degree PF, % SS Core R&DT_101007_40_1_0 50 40 0.697 13.93 15 83.4 N R&DT_101026_41_1_0 41 14.24 15.5 84.0 “ R&DT_101101_40_1_1a 13.95 83.8 Ya R&DT_101101_40_1_1b 17.5 85.1 a Stainless steel core used was 9.525 mm x 25 mm in size. 13 May 2011, FNAL-CERN CM1 Strand and Cable

Cable development Rectangular Nb3Sn To verify the impact of the cabling process on the actual superconductor that will be used in the magnet short model two 40 strands superconducting cables were produced. Strand design RRP 108/127, 0.7 mm The appropriate electrical and microstructural characterizations were done Cable Traveler Name Length, m Lay angle, degree PF, % SS Core Cable width ±σ, mm Cable thickness ±σ, mm R&DT_101109_40_1_1 6.71 15 83.7 Ya 14.61±0.02 1.331±0.003 R&DT_101112_40_1_0 7.5 82.8 N 14.62±0.02 1.328±0.003 a Stainless steel core used was 9.525 mm x 25 mm in size. 13 May 2011, FNAL-CERN CM1 Strand and Cable

No. cross sections analyzed Min./Max. Merged subelements Damage Analysis Cable name RRP Strands used No. cross sections analyzed Strands w/Damage Broken subelements Min./Max. Merged subelements Damaged subelements R&DT_101109_40_1_1 (w/core) 108/127 6 1 2 0/2 R&DT_101112_40_1_0 (no core) Cable cross section with core 6 cross sections of each cable (with and without core) are studied. Both cables show very little internal damage. These cables show less than average strand damage. Damage Details 13 May 2011, FNAL-CERN CM1 Strand and Cable

Electrical characterization Rectangular with core In VI Tests, solid markers stands for Iquench evaluated from full transition, whereas empty markers stands for the maximum current reached by sample before quench with no visible transition. Ic, Jc @14T Ic , Jc @12 T Is 0-4T Is 4-8T RRR Extracted Cored cable #1 288,1626 468,2643 950 575 Extracted Cored cable #2 248,1400 424,2400 925 975 182 Round 275,1553 455 ,2570 1175 775 13 May 2011, FNAL-CERN CM1 Strand and Cable

Electrical characterization Rectangular without core In VI Tests, solid markers stands for Iquench evaluated from full transition, whereas empty markers stands for the maximum current reached by sample before quench with no visible transition. Ic,Jc@14T Ic ,Jc@12T Is 0-4T Is 4-8T RRR Extracted UnCored cable #1 282,1593 464 ,2620 1225 800 Extracted UnCored cable #2 262,1479 414 (Imax) 1200 725 232 Round 275,1553 455,2570 1175 775 13 May 2011, FNAL-CERN CM1 Strand and Cable

Keystoned cables After the first stage of rectangular cable study was completed and the new rollers for the keystoning fixture commissioned the second stage was to make keystoned cables. The attempt to make in a single pass a keystoned copper cable was not completely successful. The cable formed but roped entering the keystone wheels in the first 80m. The decision was to finish the remaining 245m rectangular and to make a second rectangular copper cable to be wound in a practice coil. 13 May 2011, FNAL-CERN CM1 Strand and Cable

Rectangular Copper Practice Cable #2 Cable Traveler Name No. strands Strand size, mm Mandrel width, mm Cable width, mm Cable thickness, mm Lay angle, degree PF, % SS Core Length, m R&DT_110301_40_1_0 40 0.696 14.05 14.76 1.237 15 86.2 N 250 Cable was fabricated for winding a practice coil. Cable was well formed and to size Left Side view Right Side view Top view 13 May 2011, FNAL-CERN CM1 Strand and Cable

Keystoned Nb3Sn cable RRP 114/127 Nb3Sn Keystoned 40 strands cable was made in two passes. 114/127 Strand design The cable strands diameter except one was originally 1 mm drawn to 0.7 mm. In the first pass 250 m of rectangular cable was made. A piece of 15 m of the rectangular cable was cut and annealed in argon atmosphere for 1 hour at 180 ºC. The two cables , annealed and not, were keystoned. Microstructural analysis of cable cross sections and electrical characterization of extracted samples were performed. Keystoned no annealed RRP 114/127 Keystoned annealed Cable Traveler Name Type Length, m Mandrel width, mm Lay angle, ° PF, % Cable width±σ, mm Cable thickness±σ, mm R&DT_110315_40_1_0 R 248.4 13.92 15 84.04 14.556±0.038 1.316±0.009 Ra 84.1 14.599±0.039 1.309±0.005 K 230 - 86.3 14.71±0.012 1.265±0.005 Ka 85.8 14.69±0.02 1.274±0.005 a Rectangular cable has been annealed in Argon at 180 Cº for 1 hr 13 May 2011, FNAL-CERN CM1 Strand and Cable

Damage Analysis Nb3Sn KS Cable Rectangular Keystoned Rectangular Reacted Keystoned reacted Keystoned Annealed Reacted Several cross sections from keystoned, rectangular, keystoned annealed, reacted and unreacted cable were analyzed. Rectangular cable edges 13 May 2011, FNAL-CERN CM1 Strand and Cable

Damage Analysis Nb3Sn KS Cable (cont’d) Cable Traveler Name Type Reacted No. CS No of Strands w/ possible damage Total No. broken subelements Min/Max. No. merged subelements No. Damaged Subelements R&DT_110315_40_1_0 R N 6 0/0 K 4 15 5/5 Y 1 2 13 14/14 16 Ka 3 0/2 a Rectangular cable has been annealed in Argon at 180 Cº for 1 hr 6 cross sections of each Type (Rectangular, Keystoned, Keystoned annealed) are studied. Keystoned cable shows an average strand damage. The annealed cable shows less than average strand damage. 13 May 2011, FNAL-CERN CM1 Strand and Cable

Electrical characterization Nb3Sn KS Cable Ic ,Jc@ 14 T Ic ,Jc@ 12 T Is 0-4T Is 4-8T RRR Keystoned 9772-2A #1 HT269 266, 1382 442, 2297 925 750 150 Keystoned 9772-2A #2 HT269 268, 1393 447, 2323 1300 825 280 KS Ann. 9772-2A #1 HT270 302, 1569 482, 2505 950 >900 230 KS Ann. 9772-2A #2 HT270 307, 1595 489, 2541 196 Rect. 9772-2A #1 HT270 306, 1592 493, 2564 Round 9772-2A HT 269 260, 1351 440, 2287 Round 9772-2A HT 270 267, 1388 451, 2344 1475 1000 300 In VI Tests, solid markers stands for Iquench evaluated from full transition, whereas empty markers stands for the maximum current reached by sample before quench with no visible transition 13 May 2011, FNAL-CERN CM1 Strand and Cable

Cable Readiness Review An internal readiness review of the 11 Tesla dipole cable was held on May 02, 2011. The following aspects were reviewed: Procedure Documentation (Traveler, Logbooks) Infrastructures (Cable Machine, Tooling) Overall their were no major or minor findings Starting cable fabrication for the demonstrator coils Front page of the cable traveler 13 May 2011, FNAL-CERN CM1 Strand and Cable

Cable Map   OXFORD RRP 108/127 BILLET # SIZE METERS DATE REC. 13062-1 0.7mm 636 Mar.23.11 13062-2 554 13062-3 952 13062-4 443 13062-5 359 13062-6 1998 13062-7 1012 13062-8 2793 13063-1 2411 13063-2 722 13063-3 3625 13063-4 2273 13063-5 713 13090-1 469 13090-2 2011 13090-3 601 13090-4 784 13090-5 2456 TOTAL 24812   OXFORD RRP 108/127 BILLET # SIZE METERS DATE REC. 12292-1 0.7mm 1871.5 Aug.31.10 12292-2 1665 12292-3a 600 12292-3b 700 12292-3c 2776 12292-3d 567 12319-1a 1647 12319-2 2140 12521-1 410 12521-2 2599 12522-1 427 12522-2 462 12522-4 714 TOTAL 16578.5 1 UL→ 210 m 3 UL for a long cable + 1 UL + 60 m for the analysis Cable fabrication for 11T Demo Coils in progress 13 May 2011, FNAL-CERN CM1 Strand and Cable

Summary Cable has been designed Technology developed and experiments verified Reviewed Cable Fabrication in progress 13 May 2011, FNAL-CERN CM1 Strand and Cable

R&D steps Fabrication and test of Cored Cables Longer UL (650 m) for 5.5 m long coil New Strand Design RRP-151/169 from OST R&D strand from Hyper Tech, Inc. PIT strand from CERN 13 May 2011, FNAL-CERN CM1 Strand and Cable