Mechanical stability and QXF coil winding P. Ferracin, L. Oberli, S. Izquierdo Bermudez MQXF Conductor Review November 5-6, 2014 CERN

Outline Winding test set-up and results Coil winding experience at CERN Paolo Ferracin 5/11/2014

First test set-up GEOMETRY 2: GEOMETRY 3: GEOMETRY 1: POLE INNER LAYER GEOMETRY 2: BIG SPACER INNER LAYER GEOMETRY 3: POLE OUTER LAYER Paolo Ferracin 5/11/2014

Second test set-up Paolo Ferracin 5/11/2014

Second test set-up Layer jump Paolo Ferracin 5/11/2014

Third test set-up Inner layer, favourable Outer layer, unfavourable Paolo Ferracin 5/11/2014

Exampled of unstable cable Paolo Ferracin 5/11/2014

Winding test example (with tool) Paolo Ferracin 5/11/2014

Winding test example (with tool) Paolo Ferracin 5/11/2014

“Parameter space” Nominal Min. – Max. Mid-thickness Width 1.525 mm tolerance: +/- 0.010 mm Width 18.150 mm tolerance: +/- 0.050 mm Keystone angle 0.55 deg. tolerance: +/- 0.10 deg. Pitch length 109 mm Min. – Max. Mid-thickness 1.430 - 1.570 mm Width 17.800 - 18.330 mm Keystone angle Rect. - 0.36 - 067 deg. Pitch length 95 - 125 mm Paolo Ferracin 5/11/2014

45 winding tests performed Paolo Ferracin 5/11/2014

45 winding tests performed Paolo Ferracin 5/11/2014

Winding test conclusions By P. Ferracin, L. Oberli, S Winding test conclusions By P. Ferracin, L. Oberli, S. Izquierdo Bermudez In general, all RRP and PIT cables are stable in the favorable direction Cable wound clock-wise around the pole (inner layer condition) In general, all RRP and PIT cables are unstable in the unfavorable direction The few PIT which did not show unstable behavior were not reproducible The cable behaviour was not improving by changing winding tension We performed tests at different winding tension (25 kg, 45 kg, 60 kg), and the behaviour was similar The core does not seem to play a role in the cable mechanical stability We only wound one RRP sample without core, but “typical behaviour”. In general, all RRP and PIT cables can be wound with the tool (CERN) and/or with the binder (FNAL) In some cases it is required to use a thinner tool which better follows the cable during all the length of the turn Paolo Ferracin 5/11/2014

Outline Winding test set-up and results Coil winding experience at CERN Paolo Ferracin 5/11/2014

Coil fabrication status: 3+3 coils wound and cured LARP coil #1 completed LARP coil #2 completed LARP coil #3 Prep. For impregnation at BNL CERN coil #001 Prep. For impregnation CERN coil #101 Prep. For impregnation CERN coil #102 Prep. For reaction Paolo Ferracin 5/11/2014

Mandrel and pole set-up Paolo Ferracin 5/11/2014

Mandrel and pole set-up Paolo Ferracin 5/11/2014

Mandrel and pole set-up Paolo Ferracin 5/11/2014

Inner layer winding Pole insulation 0.175 mm S2 glass, 33TEX, 493 sizing, 19 mm wide Paolo Ferracin 5/11/2014

Inner layer winding Layer jump Paolo Ferracin 5/11/2014

Inner layer winding Voltage taps Paolo Ferracin 5/11/2014

Winding with tool Paolo Ferracin 5/11/2014

Winding with tool Paolo Ferracin 5/11/2014

Winding with tool Paolo Ferracin 5/11/2014

Winding with tool Paolo Ferracin 5/11/2014

Winding with tool Paolo Ferracin 5/11/2014

Inner layer winding Ceramic binder Paolo Ferracin 5/11/2014

Ceramic binder during winding CTD-1202X From the technical specification Curing 1 hour at 80°C + two hours at 150°C We noticed that if we cure at T < 150°C, after 10 minutes the cable is still wet and the insulation is not rigid. Paolo Ferracin 5/11/2014

Ceramic binder during winding Procedure Paint binder on the cable Heat the cable on one side, and time 3 mins (after 3 mins, the cable temperature is ~150°C) Heat the other side 3 mins.   The cable is still wet and the insulation is not rigid. We cut the insulation and the fibers are not glued (very similar behaviour in the region with and without). Paolo Ferracin 5/11/2014

Ceramic binder during winding We repeated the process, heating up to 250°C, but the cable is still wet and the insulation is not rigid So Coil 001: with ceramic binder Coil 101 and 102: no ceramic binder Paolo Ferracin 5/11/2014

End spacers Paolo Ferracin 5/11/2014

Wedges Paolo Ferracin 5/11/2014

End-shoes Paolo Ferracin 5/11/2014

Ceramic binder for curing inner layer Paolo Ferracin 5/11/2014

Curing inner layer Paolo Ferracin 5/11/2014

Curing inner layer Paolo Ferracin 5/11/2014

First Nb3Sn coil (101, low-grade RRP) Outer layer after curing Paolo Ferracin 5/11/2014

First Nb3Sn coil (101, low-grade RRP) Outer layer after curing Paolo Ferracin 5/11/2014

First Nb3Sn coil (101, low-grade RRP) Outer layer after curing Paolo Ferracin 5/11/2014

Coil winding conclusions The feed-back from the winding team about the stability of the insulated RRP cable during winding of coil 101 and 102 is extremely positive No clear popped-out strands were observed, also by partially unwinding some of the turns Similar conclusions come from LARP, which has wound 3 coils with RRP strand using the binder (and not tool) From the winding team, it seems also clear that the braided insulation plays a key role in improving stability However, it is not clear if, by simple visual inspection and touching the insulated cable during winding, a popped strand can be detected CERN coil 101 (low grade RRP) and LARP coil 1 will be cut to check Paolo Ferracin 5/11/2014

Appendix Paolo Ferracin 5/11/2014

Winding with twist ~90 degrees in 150-200 mm, tightening the cable Paolo Ferracin 5/11/2014

Winding with twist ~90 degrees in 150-200 mm, tightening the cable Paolo Ferracin 5/11/2014

Winding with twist ~90 degrees in 150-200 mm, tightening the cable Paolo Ferracin 5/11/2014

Winding with twist ~90 degrees in 150-200 mm, tightening the cable Paolo Ferracin 5/11/2014

Winding with twist ~90 degrees in 150-200 mm, tightening the cable Paolo Ferracin 5/11/2014

Winding with twist ~90 degrees in 150-200 mm, tightening the cable Paolo Ferracin 5/11/2014