1. Stave - Electrical Break Richard French The University of Sheffield Material from the ATLAS SCT/IBL/PIXEL community

2. Location of cooling components and pipe destinations in ATLAS Services routing of current ID from PP2 How much of the wheel needs reinventing? Can we tweak an existing design? For reference – is the positional terminology the same? Existing ATLAS layout and terminology to jog memory

3. Electrical break on barrel was done with Beryllia. Cooling pipe was copper-nickel. Upgrade uses Titanium as a baseline for Stave core. CuNi was used for on detector pipework Do we have a baseline (CP2 Ti)? Stainless steel (austenitic) was used for off detector What is our baseline? 316L? C106 soft annealed copper was also used in small amounts for manufacture of Heat Exchangers (HEX), S bends and other short lengths of tube both on and off detector Not ideal. Unfilled PEEK tube (specially made 12mm ID 13mm OD) was used for gas ‘guidance’ of N2 dry gas around the detector. Not thought about yet for N2 delivery. Existing materials used in ATLAS SCT cooling system Items to consider before addressing design of electrical break connector GALVANIC STABILITY OF THE SYSTEM

4. Endcap disks have ground referencing tapes that bond together the complex cooling tube paths. SCT Endcap Grounding and Shielding Scheme

5. https://indico.cern.ch/getFile.py/access?contribId=5&resId=0&materialId=slides&confId=206624 Life gets much simpler with the current proposal from Ned. Location of electrical break does not matter so either at PPB0 Or PPB???? 1ish. Decided at RAL meeting to concentrate at end of Stave option. Mass implication? Materials choice CRITICAL JOINT Encapsulate connector at end of Stave OD??? Diameter transition

6. Quick peek at IBL progress 3 connector types Brazed union De-mountable connector with swaged tube Electrical break (brazed ceramic) OD crucial to encapsulation in Stave. Conductivity with carbon fibre skins

8. IBL Electrical Break and Connectors 2.5 to 1.7 OD 1.7 to 2.2 OD 1.7 and 2.2 OD

9. 316L tube – ceramic – titanium tube isolator Diameter transition of tube OD can be reduced Length ok Can be encapsulated Need to better understand purpose of covers. Attempt to make simplified, similar item using brazed ceramic Material type? Reduce size Ti to Ti joining preferred as simpler OD/ID v working pressure Volume / Quantity required to fit with new programme? Services mock up? Introduce to prototype staves. 2.5 1.7