IN2P3

Why Titanium for cooling circuits? Titanium material collect the most important criteria for cooling circuit design: Low CTE: important parameter to reduce material necessary for geometrical stability and improvement of material delaminations Good Thermal conductivity: essential for thermal performances and material economy Non corrosive Good weld ability Good Bend ability Ultra thin pipes can be produced High mechanical characteristics Low activation under irradiation X0% more interesting the Stainless Steel ( X0 Ti /X0 316 L ≈ 2  2 mm ID, 0.1mm Thickness Ti pipe  2mm ID, 0.05mm Thickness 316L pipe for material conservation)

Progress IN2P3 (LAPP, CPPM) Several Batches have been produced and IN2P3 All pipes were Minitubes (Grenoble, France) but price is very high. A new vendor (UK, Schefield) Is under qualification for IBL Welding process for joining is well controlled (Laser and EB welding have been tested with success) Bending process have been tested with success needs more improvement if small bending radius needed

Welding process Both Laser welding and Electron beam have been qualified The two techniques require a controlled gap between the pipe and the fitting to avoid shrinkage Specific cleaning has to be applied to avoid welding porosity The last test made was perfect in terms of weld quality and has been tested under CO2 conditions (150 Bars proof test & -50°C thermal shocks) EB welding Laser welding

Bending Process Partial Bend test was made with success using sand filling and manual bending operation (same technique used for pixel piping) Ti pipes annealing is more complex due to high temperature and risk of oxide formation (vacuum or controlled atmosphere needed) More work remain to be done to optimize the technique, but no show stopper

Toward Upgrade Type and dimension of Ti pipe have been almost frozen for IBL Project Meanwhile some R&D could be done to minimize material involved by Ti piping: Pipe distribution, actually one pipe is used/stave in the barrel we could study the pipe sharing between two or more stave structures Pipe thickness is linked to the maximal pressure applied and inside diameter  optimization of the cooling parameters (pipe ID) would permit to get thinner pipes (the production limit is about 0.05mm thick Minitubes company)  Thickness can be reduced linearly with the inside radius

Toward Upgrade New Ti alloys should be also investigated while some grade gives higher mechanical resistances  close collaboration with manufacturers

8 Pipes order Titanium (ordered) Type 1 : ID : /-0.00mm Thickness : /-0.00mm Nom OD = 2.275mm 3 m (+/-10.00mm) X 20 pieces (total length 60m) £46.75 per metre = £2805 Type 2 : ID : /-0.00mm OD x /-0.00mm Nominal Thickness = 0.20mm X 3 m (+/-10.00mm) X 20 pieces (total length 60m) £49.50 per metre = £2970 Delivery ?