1 - NbTi-Nb transitions for the extremities (Clé et Bords droites): DESIGN OF THE WELDING CONFIGURATIONS & SAMPLES FOR TESTING AND QUALIFICATIONS: - Tuning Interfaces: Possible change of design to weld directly Niobium with Niobium: Nb-NbTi & Nb-Nb both options will be tested NbTiNb - Nb-Nb Final ellipsoidal welds (Clé et Bords droites):

2  MANUFACTURING OF THE WELDING TESTS & TOOLING for testing ON-GOING  Drawings available: EDMS

The HiLumi LHC Design Study is included in the High Luminosity LHC project and is partly funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement Crab Cavities: In-house Production Shaping J-P. Brachet L. Prever-Loiri, A. Carvalho, V. Gerbant, M. Garlaschè, L. Giordanino, R. Leuxe … S. Atieh, A. Cherif, R. Claret, P. Freijedo, S. Langeslag, T. Tardy …

4 Lunette:

5 Shaping Lunette: Status Pressing Holders Sheet works in traction Tool #1.2 Different tests performed (Cu): - Gap between blank holder and sheet - Presence / absence of holder Shape precision Sheet thickness Ref. EDMS Test #9 SECT Z+ SECT X+ SECT Z- SECT X- Band =1.4mm thickness MIN =3.64 RF ÷3.73 EXT Band =0.5mm thickness MIN =3.35 RF ÷3.56 EXT Test #4

Ø Int = H1 = Ecart = H3 Ø Est = H1 = Ecart = Ø Est = H2 = Ecart = Ø Est = H3 = Ecart = 0.08 «Lunette n° 11» H2 H1 Ø Est THEO= Ø Int THEO= Ø=+0.1mm in elliptical tool Ø Int ~= H1 ~= 17 Ø Int ~= H1 ~= 20

SECT Z+ SECT X+ Section X+Section X-Section Z+Section Z- Err max profile Est Err min profile Est Err max profile Int Err min profile Int Err max RF profile EST Err min RF profile EST Err max RF profile INT Err min RF profile INT Ø int profile Est Ø int profile Int Ø est profile Int Ø est profile Est Thickness INT edge Thickness EXT edge Thickness INT RF edge Thickness EXT RF edge Planarity of INT flat surface Planarity of EXT flat surface SECT Z+ SECT Z- SECT X- Ø est Pint Ø est Pest Ø est Pint Ø int Pint Ø int P est Ø int P int Ø est P int Ø est P est Ø int Pest Ø int Pint Ø est P est Ø est P int Øint P int Ø int P est Ø int Pest Flatness for machining/weld tool SECT Z- SECT X+ SECT X Due to shape error at extrusion Overall shape and thickness are good! Correcting Radius shape via stamping (matricage). Circular Test pending

8 Cuvette:

9 Cuvette: Tool # 4.2 Results Cu tests performed to explore influence of : - Gap between blank holder and sheet -Presence / absence of holder Forming ratio results are promising Shape accuracy still not satisfactory As expected, blank holder and Ø EXT have great influence on thickness (& shape) … Further tests foreseen to optimize parameters for highest thickness  tool remachining Holder: 1mm gap Screws: 50Nm Holder vs. Free: 50/50 % Thickness MIN ~= 3.6mm

10 Extrusion Lunette 6x punches Tool #3.1 (& #3.2) Cu samples ready Last subcontracted parts by Friday (2WK delay)

11 Diabolo Steel Adiprene Steel Calculations being finalized for punching forces, tool sizing, shape of punch Planning: OK, prearranged DO closes today. Best bid 6-8WKS! REMINDER: piece on critical path

12 Diabolo: forming procedure

13 Material: Supply for Production 1 st batch of Nb sheets (Ningxia) CERN – 3mm, 4mm, 15mm, 25mm ISSUE: On 3x+3x sheets, local inclusions grinded manually to thicknesses below requirements Areas to be used for testing 1 st batch of NbTi sheets (Ningxia) : expected beg. WK9 – 15mm ISSUE: 15mm will actually be 13mm… OK for prod but 1mm thickness of margin 2 nd batch of Nb sheets (T. Denkai) : delivery end Feb. Still missing: NbTi for tuning bananas Greenlight of purchase once positive Weld results

14 Conclusions Shaping Test campaign ongoing Lunette results very promising Cuvette results good for forming ratio but shape and thickness to be improved Planning: Extrusion and Cuvette (#2 circular) -- delays still not critical Need to launch: Cuvette (#3 circular) Lunette (#1 circular) matricage test Lunette Elliptique Watch out for Diabolo Open points: Material for tools Machining + Welding : stress free or not Butt weld vs. Lip Machining : internal & external Single parts : design for production