CHAMONIX XV QRL installation and first experiences of operation G. Riddone on behalf of the QRL team AT/ACR-cd Acknowledgements to AT/ACR-op and AT/ACR-in sections, AT/VAC, AB/CO, TS/IC, TS/SU groups for their support and collaboration

GR, AT/ACR-cd 2 Contents QRL layout Installation »Main features »Present status »Schedule Operation  Reception tests »Schedule »Main results Conclusions

GR, AT/ACR-cd 3 QRL layout Tested part is marked in blue A G F E D C B H I A - Vacuum sub-sector “A” QRL is a continuous cryostat of ~3.2 km length no header (4 or 5) sectorisation  9 vacuum sub-sectors (A…I)  vacuum insulation separate from machine QRL elements in one sector ~ 38 service modules ~ 40 fixed point/vacuum barrier elements ~ 235 straight pipe elements ~ 10 steps/elbows ~ 1-2 cryogenic extensions

GR, AT/ACR-cd 4 QRL layout Sector 3-4 Sector 5-6 Pipe element Service module

GR, AT/ACR-cd 5 QRL sector installation Installation of ~ 700 external supports Positioning of ~ 325 elements Welding and testing of ~ 325 interconnections  > 2000 welds »~ 180 “O” type interconnections (1 butt-weld per header) »~ 75 “C” type interconnections (2 butt-welds per header) »~ 70 “A” type Interconnections (3 welds per header)

GR, AT/ACR-cd 6 QRL sector installation Overall installation: 6 teams Installation by sub-sectors Automatic welding for the inner headers »Nominal rate: 20 int./week »Achieved rate: 30 int./week Manual welding of the external sleeves »Nominal rate: 20 int./week »Achieved rate: 35 int./week NDT tests »Internal (video camera) and external visual control: 100% »Radiography tests: from 100 % to 10 % as a function of weld quality »Leak tightness tests: 100 % (each weld, each sub-sector, each sector) Head of the machine Tool for He leak test

GR, AT/ACR-cd 7 Status of the installation

GR, AT/ACR-cd 8 Schedule

GR, AT/ACR-cd 9 Reception tests QRL tests: »Sector 7-8, sub-sectors A and B: about 700 m »Sector 8-1, full sector: about 3200 m Tests »Pressure tests »Flushing of the circuits »Cooldown »Instrumentation commissioning »Heat inleak measurements »Warmup

GR, AT/ACR-cd 10 Reception test schedule

GR, AT/ACR-cd 11 Pressure test Sector 8-1

GR, AT/ACR-cd 12 Configuration for flushing and cool-down

GR, AT/ACR-cd 13 High-flow rate flushing with He Original colour ! New filter (8-1) Old filter (7-8, A-B)

GR, AT/ACR-cd 14 QRL layout for reception test

GR, AT/ACR-cd 15 Tests for the sector 8-1

GR, AT/ACR-cd 16 Cool-down Valve blockage by a “plastic film” coming from header B

GR, AT/ACR-cd 17 Thermometer validation Header C, SSA: 8 TT fully in accordance

GR, AT/ACR-cd 18 Heat inleak measurement Q B,C,D = (mD·hD+mB·hB) - mC·hC (indirect calculation of the mass-flow by using the heaters EH) Q EF = mF·(hFout-hFin) + mE ·(hEout-hEin) B, C and D E and F

GR, AT/ACR-cd 19 Results for headers E and F Boundary conditions »Insulation vacuum in the main envelope: mbar (8-1) mbar (7-8) »Headers E and F: K »Headers C, D and B: 8-15 K [W]Sector 7-8Sector 8-1 Calculated Measured2250 +/ /- 400

GR, AT/ACR-cd 20 Results for headers C, B, D (sector 7-8, A and B) - without JR and without JC ~ 0.25 W/m - JC ~ 50 W  4.2 W/JC - JR ~ 70 W  1 W/m Measurement cross-checked with independent refrigerator input JC = jumper connection JR = junction region

GR, AT/ACR-cd 21 Results for headers C, B, D (sector 8-1) Boundary conditions »Insulation vacuum in the main envelope: mbar »Headers E and F: K »Headers C, D and B: 8-15 K [W] B+C+DBCD Calculated Measured [+/- 30] Measurement cross-checked with independent refrigerator input Mass-flow cross-checked by using the valve opening QRL with JR and without JC

GR, AT/ACR-cd 22 Results for headers C, B, D (sector 8-1) - without JR and without JC ~ 0.16 W/m - JC ~ 90 W  2.4 W/JC - JR ~ 35 W  0.4 W/m

GR, AT/ACR-cd 23 Temperatures of the vacuum jacket

GR, AT/ACR-cd 24 Conclusions 1/2 Installation progresses well: »External support installation at 75 % »Element installation at 50 % Installation in the sectors 3-4 and 5-6 (JR excluded) meets the target rates At present the main concerns for the installation are: »delay for leak detection and repair »availability of singularities for the sector 1-2 (2 JR  18 elbows/steps) »installation of the QRL in UJ22 and UJ24 and possible interference with magnet transport: tooling for QRL installation shall allow the magnet transport Pressure tests successfully performed for sectors 7-8 (A+B), 8-1 and 4-5 (without the JR) Flushing of headers required and sufficient time shall be allocated

GR, AT/ACR-cd 25 Conclusions 2/2 Cold reception tests performed for sectors 7-8 (A and B) and 8-1 Successful thermo-mechanical validation of the QRL design Thermometer accuracy of about +/- 50 mK, much better than specification (+/- 1 K for T> 6K) Heat inleaks to K (headers E and F) circuit within specification For sector 7-8 (sub-sectors A and B) heat inleaks to 4-20 K (headers B, C and D) above specification. Possible causes identified: »Higher thermal shield temperature than expected »Higher insulation vacuum than nominal »Not nominal insulation vacuum in the jumpers: impact on the heat flux through MLI For sector 8-1 heat inleaks to 4-20 K circuit are within specification »Important: Header B heat inleaks within the specification (QRL heat inleaks represents more than 95 % of the corresponding total budget) Other QRL sectors cold tested with the cryo-magnets: still possibility to measure the heat inleaks to the headers only (at present no allocated time for this test)