LEAK TESTING in SMACC Cold vacuum system recall Phase 1, 2 & 3 VSC activities Resources, Infrastructure Still to do Paul Cruikshank on behalf of TE-VSC Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

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LHC arc cold vacuum systems - recall 3 Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

LHC arc cold vacuum systems - recall 4 Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

LHC arc cold vacuum systems - recall 5 LHC magnet cryostat QRL cryostat Jumpers Vacuum barriers Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

LHC arc cold vacuum systems - recall 6 Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

LHC arc cold vacuum systems - recall 7 LHC cryostats were designed with DN100 ISO-K ‘pumping’ ports at vacuum subsector extremities. 300l/s turbos can be installed (and removed) without breaking vacuum Tunnel equipment: 63 m 3 /hr mobile primaries – 20 units 300 l/s mobile primaries – 40 units MS Leak detectors – 20 units Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

LS1 leak test support & consolidation - cold vacuum 8 IC status Arc splice train - LT support LHC cons - LT support DFBA - LT support VSC IV consolidationVSC cold BV cons Closed (phase 1) Degrade IV, Vent IV, LT (80 K < T <300 K), Localise known He leaks, He & RGA analysis Vent BV, RF ball, Open (phase 2) M clamshell, Cryomagnets, CC, Y, Diodes Splices & lyra, DFBAK, Flexibles, Localise He leaks (5 bar), Vent QRL & SAM, Flap valves, DN200 springs & pumpouts, Reclamping of DN100 & 63, Additional by-passes & turbos, Turbo maintenance, Pump & LT QRL & SAM, PIM temp protection, PIM exchange, Rupture discs, RF ball, Pump & LT BV, Protection shells, Closed (phase 3) Pump IV, LT envelope, LT internals, LT after PT, LT envelope, LT internals, LT after PT, LT envelope, LT internals, LT after PT, before train time window - typical activities in an arc Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

LS1 leak test support & consolidation - cold vacuum 9 IC status Arc splice train - LT support LHC cons - LT support DFBA - LT support VSC IV consolidationVSC cold BV cons Closed (phase 1) Degrade IV, Vent IV, LT (80 K < T <300 K), Localise known He leaks, He & RGA analysis Vent BV, RF ball, Open (phase 2) M clamshell, Cryomagnets, CC, Y, Diodes Splices & lyra, DFBAK, Flexibles, Localise He leaks (5 bar), Vent QRL & SAM, Flap valves, DN200 springs & pumpouts, Reclamping of DN100 & 63, Additional by-passes & turbos, Turbo maintenance, Pump & LT QRL & SAM, PIM temp protection, PIM exchange, Rupture discs, RF ball, Pump & LT BV, Protection shells, Closed (phase 3) Pump IV, LT envelope, LT internals, LT after PT, LT envelope, LT internals, LT after PT, LT envelope, LT internals, LT after PT, before train time window 50 %10 % 20 %10 % IS Workload - typical activities in an arc Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

Phase 1 leak testing Cryostat still closed & under vacuum Tightness status of arc IV and BV Under vacuum, > 80 K, He pressure constant, 3 days/arc Longitudinally localise known helium leaks (see later) Insulation Vacuum degradation to assist warm-up Insulation vacuum venting to tunnel air RF ball test (see C.Garion presentation) 10 Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

Phase 1 - activities 22 internal He leaks to solve 2 leaks > mbarl/s, 12 leaks > RT Highest priorities are:3-4, A27L4, coldmass circuit – very large leak should be localised quickly 4-5 QRL SubS B, line C – will need dedicated intervention scenario with CRG Note:- the LHC operates with these leaks; - the 2 biggest leaks weren’t present at RT after welding and PTest; - for many of known leaks, search in 2006 & 2007 was not successful , but they have not evolved. - previously eliminated leaks a) at welds - incomplete, inclusions, porosity, LME, etc b) others - shocks, inclusions, false arcs, ultrasonic vibrations, etc 11 Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

Longitudinal leak localisation - which IC to open? 12 An under vacuum leak test in molecular flow conditions, using turbomolecular pump, mass spectrometer leak detector and helium as tracer gas. Assume linear conductance of cryostat, so C  1/L (with & without MLI) For S >> C1 or C2: q1/q2  C1/C2  L2/L1 For LHC cryostats, S ~ C so apply correction for effective pumping speed Experience shows method is not perfect to one interconnect! Additional adjacent interconnects were often opened to localise the leak. Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

Phase 1 - Leak testing Known internal leaks: Re-measure the known internal helium leaks before venting: Cryostat under vac, temp > 80 K, He pressure constant, Two 8 hour days per known leak with above conditions. Need CRG support to pump and pressurise circuits. Leaks in the same arc can be treated in parallel After RT, MSC to open 5 priority interconnects/leak (1 day). VSC will need pressure ~ 6 bar in cold mass & c’k circuit for 2 days. Co-activity with ‘special intervention team’ needs to be co-ordinated. 13 Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

Clamshells – recall ~20 diameters and diameter combinations for LSS standalones NBR, polyurethane, silicone rubber, metal+mastic 14 Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

Clamshells Support rings for asymmetrical models Sealing on non-perfect tube surfaces: –alcohol for small defects to allow a E-8 mbar.l/s residual signal to reduce to E-10 range –mastic for bridging gaps –vacuum grease for intermediate defects (e.g. surface scratches) Same space as orbital welding machine 15 Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

Phase 2 - Leak testing in train Leak test all new welds before W closure: Validate beam vacuum – new PIMs Validate 100% M welds with clamshell – 60 IC/week Validate 100% other new welds with clamshell (new magnets, etc. ) Treat non-conformities with MSC special intervention team (& MME) 16 Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

Phase 2 - Clamshells on M Technical challenges: ~ 10’000 M welds to clamshell Want to develop & validate a ‘long clamshell’ to test both M welds How to supply He into 214 m cold mass volume (also pump out of air)? Baseline - via one unwelded M sleeve Special interface tool to develop – modified clamshell, Local pumping system and backfill (~ 6 m 3 ) from He bottle, Option 1 - via M2N hose – must be cut & rewelded – 13 positions/arc Option 2 - via QRL – when available (R2E, cryo maintenance) Any ‘holes’ in 214 m cold mass envelope will block clamshell test (& train) eg M lines, N connection box at SSS, jumper, diode, DFBA Second pass required after final M sleeve is welded Expect between 10 to 50 leaks on M welds (installation statistics). 17 Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

Phase 2 - LT Support - SIT & DFBA Special intervention team Cryomagnet exchange (MB & SSS) = V, X, E, N, C’, K lines Y repairs = X, CCryostat, diodes, Q6 He level gauge, Q1 braids, Clamshells and special tools exist Dedicated VSC team DFBA Main splices, lyras, flexible hoses K volume of DS Pigtails – 4.5 K bath – independent closed He volume DFBAK HCM removal – above plus jumper & LCM interconnect, Clamshell geometries to develop, beam vacuum equipment to remove. Dedicated VSC team(s) IV & BV Other challenges: Closed volumes can be pumped and backfilled (& pressurised) with He Open volumes must be injected with He just prior to welding then clamshelled on-line. 18 Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

Phase 3 - Leak testing after W closure Evacuate & global leak test all insulation vacuum subsectors after W closure: Evacuate with mobile groups Validate cryostat envelope – W, DN200, new magnets, reclamping, etc Validate internal helium circuits at 1 bar – M, N, new magnets, Y, etc. Need helium via QRL, all headers of sectors closed A closure rate of 60 IC/week gives ~ 12 vacuum subsectors in parallel Validate internal circuits after P.Test at 50% of design pressure Treat any non-conformities with MSC special intervention team & CRG Duration of 2-3 weeks/vacuum subsector – expect internal leaks/arc. 19 Leak imported from phase 2: Clamshell not possible, Clamshell poor sensitivity, Interconnection damage Leak opened by outgassing or Leak opened by P.Test Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

Documentation Procedures: Existing procedures for arc & LSS leak testing Existing maintenance procedures for pumping groups Existing procedures for vacuum degradation Existing procedure for relief spring installation Need to produce generic procedure for clamshell tests Data storage: Use of WISH tool to define status of leak test tasks Create NCR in edms in case of leak and attach to WISH step Maintain test/activity details in VSC Excel files – who, what, when, Team leaders in the tunnel send daily reports Maintain overview table of subsector status, List of known He leaks – NCR in edms 20 Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

Resources summary VSC Staff 2 Engineers, 1 Fellow, 5 technicians Vacuum support contract S industrial support staff required for ins vacuum system (& B.Vac) arc activities in 2013, then reduction will depend on agreed planning. FSU support (FSU-TE-09,S145) 0.5 additional workshop mechanic for PIM activity (+0.5 for expts) Polish collaboration 6 eng/technical staff for cold beam vacuum interconnect QA inspection at opening/closing, beam vac temporary protection, endoscopy at PIM cutting positions install protection shells  All will require safety training, access training, safety equipment Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

Infrastructure needs Bungalows/office space: Office space at even points only (shared with VSC-LBV) CERN wireless intranet & telephone QA, doc, tech meeting, storage of sensitive equipment Polish Collaboration – all equipment provided by VSC cars, bikes, trailers, safety equip, PC, cameras PEFRA; 3 dedicated VSC Pefra at each even point from tunnel access date. -for mobile pumping groups, detectors, tooling – shared with LBV. Dedicated VSC/EIV logistics zone on surface: At each even point, 5m2 storage & 14 bicycles & 5 trailers. 22 Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

Still to do in 2012 Optimise phase 1, 2 & 3 activities with SMACC & LS1 coordination Complete inventory of SIT & DFBA tasks Continue procurement of additional clamshells Develop tooling for helium injection at unwelded M sleeve. Expand, integrate, equip & train IS, FSU, & PL teams Create ECRs Complete QA procedures Complete PPSPS, Safety Folder, DIMR, Other? 23 Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

Thanks for your attention. 24 Paul Cruikshank TE/VSC Leak Testing in SMACC 3 rd LHC Splice Review, Nov ‘12

VSC Consolidation – Insulation Vacuum 25 Paul Cruikshank LS1 Preparation - Insulation Vacuum 20 th June 2012 ActivityAreaMotivation (1/impact if not done) Other Groups Affected Potential conflict with splice consolidation Install Flap Valves arcs, LSS, QRL Self closing over pressure valves no Install by-pass valvesarcs 2-3, 7-8, 8-1Pumping redundancy no Install additional turbos (& cables) QRL extremitiesPumping redundancy ELno Install long cable for turbosIR3R - LSS3 Eliminate remote-restart problem ELno Localise and repair known leaksall arcsEliminate helium leaks MSC, CRGyes Leak test envelopes – cryostat & He (before & after splice repairs) arcs, LSS, QRLCheck tightness integrity CRGyes Maintain turbo pumping groupsarcs, LSS Maintenance - preventive and corrective no Inspect beam screen capillaryarc 8-1 Understand origin of helium leak no Repair gauge cabling in mid arcsall arcs Eliminate faulty gauge reading no Add pump-out portsall arcs Increase pumping speed in case of helium leaks MSCno Finalise ‘auto-restart’All arcsRestart turbos after p.cut no Minor task

VSC Support – Insulation Vacuum 26 Paul Cruikshank LS1 Preparation - Insulation Vacuum 20 th June 2012 ActivityAreaMotivation Other Groups Affected Comments Splice consolidation All arcsBusbar non-conformities Train activity Cryomagnet replacement All arcs Except 5-6,6-7 Various non-conformities MSC special intervention team IR3 DS - bypass cryostat for collimators Postponed SMI2 proto Connnection cryostat consolidation TBCBusbar protection MSC special intervention team Y-Lines repair All arcs?Cryo performance MSC special intervention team New DN200, Re-clamping of inst flanges 2-3, 7-8, 8-1, All arcs Safety conformity MSC special intervention team SAM helium gauge consolidation 6R2, 6L8Cryo control MSC special intervention team Triplet braid LSS1 & 5Cryo performance MSC special intervention team DFBA consolidation All arc ?Busbars & braids ? These projects will require extensive VSC leak testing/technical support Are they already in ‘PLAN’ ?

VSC Consolidation – Cold Beam Vacuum 27 Paul Cruikshank LS1 Preparation - Insulation Vacuum 20 th June 2012 ActivityAreaMotivation Other Groups Affected Potential conflict with splice consolidation Exchange/repair PIMSArcs, LSSEliminate critical PIMsMSCyes Install beam vac. protection shellsArcs, LSS Protection against electrical arcs MSCyes Exchange S3-4 beam screens with reversed saw teeth Arc 3-4Dynamic vacuum effectsMSC,EL,SUYes Install additional rupture discArcs SSS, LSS Protect beam vac. against overpressure no Leak test envelope- arc, LSSArcs, LSSCheck tightness integrity yes Install/remove mobile pumping groupsArcs, LSS Remove desorbed gas/recondition no Install additional gauges in arcsArcs Consolidate instrumentation ELno RF ball testArcsAperture checkno Faster closing of some sector valves Pneumatics modification ArcsReduce debris propagationno Low priority Due to synergies, some VSC resources are shared between insulation & beam vacuum arc activities

VSC Consolidation – Insulation Vacuum (not in tunnel) 28 Paul Cruikshank LS1 Preparation - Insulation Vacuum 20 th June 2012 ActivityAreaMotivation Other sections Affected Potential conflict with splice consolidation Profibus interface on mobile turbos (41) & primaries (20) Remote visibility/operation of mobile groups ICM Rebuild 10 mobile pumping groups with offset electronics Radiation hard groups in case of helium leaks ICM Equip 14 MB + 5 SSS + undulator with beam screens Replacement cryomagnets In advance of LS1 Activities outside tunnel are also added to ‘PLAN’ to have overview of all resource needs

Clamshells on M lines (1) Why weren’t M line clamshells adopted during LHC installation ? Many ‘holes’ in 214 m cold mass chain (late magnets, NCR, ELQA, etc) – late clamshell tests would stop series W closure. Masked time was available to treat leak non-conformities after W closure. Was less leak testing parallelism per arc and per sector. Why adopt M line clamshells for splice consolidation? Early feedback on weld quality in advance of W closure Little masked time available to treat leak non-conformities in global test Whole arc is closed in 4 weeks – twice rate of LHC installation peak (Most) leak identification & repair is removed from critical path In proposed LS1 planning, clamshells can be performed in masked time. If no M clamshell test – foresee several additional NC weeks in global test 29 Paul Cruikshank LS1 Preparation - Insulation Vacuum 20 th June 2012