Leak Testing QC of Cold Vacuum Systems the

Leak Testing QC of Cold Vacuum Systems the story so far………. Paul Cruikshank on behalf of TE-VSC colleagues & AL 4030 Consortium (S 133) Paul Cruikshank TE/VSC - Leak Test QC of Cold vacuum Systems - 4 th Splice Review, 23/7/2013 1

Leak Testing QC of Cold Vacuum Systems - What? Phase 1 leak test – Prior to splice consolidation (Arcs, LSS, QRL) Air to insulation vacuum Helium to beam vacuum Complete Phase 2 leak test – During splice consolidation intermediate testing of new welds: SIT, DFBA, DN 200 – on-going M lines – starting today PIM – not yet started Phase 3 leak test – After splice consolidation Global leak tests after re-closure, including pressure test Paul Cruikshank TE/VSC - Leak Test QC of Cold vacuum Systems - 4 th Splice Review, 23/7/2013 2

Leak Test QC Sequence: • Leak test executed according to procedure by trained technician, • Daily report of executed tests & results prepared by team leaders, • Result is checked by staff or COFREND certified contract support, • Result recorded and stored on TE-VSC-EIV sharepoint page, • Result recorded in WISh (where applicable), • If NOK, create NCR in MTF (staff or certified contract support), Paul Cruikshank TE/VSC Leak Testing QA SMACC QA team meeting 11/4/2013 3

Leak Testing of Cold Vacuum Systems Phase 1 - Why? Status of vacuum system tightness Localisation of known leaks Localisation of any new leaks Leak repairs in masked time Early warning of unexpected problems Paul Cruikshank TE/VSC - Leak Test QC of Cold vacuum Systems - 4 th Splice Review, 23/7/2013 4

Leak Testing of Cold Vacuum Systems Phase 1 – Helium to BV leaks Status for LHC arcs He to BV leaks S 5 -6 S 4 -5 S 6 -7 S 7 -8 S 1 -2 S 8 -1 S 3 -4 S 2 -3 0 0 0 0 Courtesy J. Finelle Paul Cruikshank TE/VSC - Leak Test QC of Cold vacuum Systems - 4 th Splice Review, 23/7/2013 5

Phase 1 – Air to IV leaks Status for LHC arcs Air leaks (identified to component) S 5 -6 S 4 -5 S 6 -7 S 7 -8 S 1 -2 S 8 -1 S 3 -4 S 2 -3 4 5 4 4 8 5 3 6 Connector feedthrough 0 -ring MB vessel at central foot B 31 L 5, A 21 L 8 C 16 R 5, A 26 L 7 B 32 L 8 Jumper weld/material Q 7 L 2 Q 29 R 2 Q 21 L 3 Q 21 R 3 Q 33 R 7 Paul Cruikshank TE/VSC Foot flange o-ring C 22 L 4 Q 6 L 8 - Leak Test QC of Cold vacuum Systems - 4 th Splice Review, 23/7/2013 6

22 ‘known’ He leaks in IV prior to LS 1 Highest priorities are: Note: S 3 -4, A 27 L 4. M, cold mass circuit S 4 -5 QRL Sub. S B, line C – repair with TE-CRG - LHC operates with these leaks - the 2 big leaks weren’t present at RT after welding & P. Test - some known leaks accepted ‘use-as-is’ due to lack of time during installation - some known leaks weren’t found to component level despite search during installation Paul Cruikshank TE/VSC - Leak Test QC of Cold vacuum Systems - 4 th Splice Review, 23/7/2013 7

Helium leak observations in IV ‘Green’ helium leak – IV pressure is rising…………. …. leak elimination will avoid perturbation to cryo system during temp transients Paul Cruikshank TE/VSC - Leak Test QC of Cold vacuum Systems - 4 th Splice Review, 23/7/2013 8

Helium leak observations in IV ‘Red’ helium leak – IV pressure rise & then limited by turbo pump speed… …leak elimination will reduce heat loads and avoid reliance on turbo pumps for pressure equilibrium Paul Cruikshank TE/VSC - Leak Test QC of Cold vacuum Systems - 4 th Splice Review, 23/7/2013 9

Phase 1 – Helium to cryomagnet IV Status for LHC arcs S 5 -6 S 4 -5 S 6 -7 S 7 -8 S 1 -2 S 8 -1 S 3 -4 S 2 -3 He to IV leak - ‘known’ (pre LS 1 data) 3+1 0+1 2+2 2+0 1+0 2+1 0+3 He to IV leak - identified to subsector 2+1(+1) 0+1(+1) 2+2(+1) 1+0(+0) 1+0(+1) 1+0 2+1 0+1(+1) He to IV leak - identified to component 2+1(+0) 0+0(+0) 2+1(+1) 1+0(+0) 0+0(+1) 0+0 2+1 0+1(+1) - Correct test conditions have allowed 4 ‘known’ leaks to be discarded. air leak near gauge, or Penning gauge error, oil vapour pressure (see later) - 4 newly observed small ‘green’ leaks may be due to correct test conditions/extra scrutiny…. - 20 internal helium leaks identified in arc subsectors after warm-up – 14 identified to component (for repair). for 6 leaks not identified to component, further tests to be performed in phase 2. - Triplet 5 L – helium leak in FF circuit (inside DFBX) stable since 2009 – propose continue ‘use-as-is’. - NC follow-up in MTF. Paul Cruikshank TE/VSC - Leak Test QC of Cold vacuum Systems - 4 th Splice Review, 23/7/2013 10

LT Phase 1 – internal leak types QQS current leads (x 1) QBQI. 9 L 2 (Q 8) M 2 N flexible (x 3) QBQI. 18 R 5 QBQI. 26 R 7 QBQI. 33 R 3 K collector (x 4) QBBI. 8 L 7, QQBI. 22 L 7, QBBI. B 34 L 7, QBBI. B 21 R 6 M weld or collar (x 3) QQBI. 13 L 6 (M 3) QQBI. 7 R 5 (M 2) QBBI. A 29 L 4(M 3) K flexible (x 3) QBBI. B 26 L 3, QBQI. 9 R 2, QBEI. 11 R 3 Paul Cruikshank TE/VSC - Leak Test QC of Cold vacuum Systems - 4 th Splice Review, 23/7/2013 11

Phase 1 – Helium to QRL IV LS 1 foreseen objectives: - Collaborate with TE-CRG to repair known (observed Dec’ 2010) internal helium leak in S 45. - Check helium residuals & air leaks after warm-up of the 72 subsectors: but, large & fast pressure rises seen in IV of 5 QRL subsectors during LS 1 warm-up, 6 additional internal helium leaks confirmed (5 not present during 2013 operation), all 7 confirmed on header C at multiply compensator. - QRL analysis/action plan/repair is on-going…………………. in shadow of SMACC Paul Cruikshank TE/VSC - Leak Test QC of Cold vacuum Systems - 4 th Splice Review, 23/7/2013 12

Phase 2 - Leak test support for M welds - Dedicated leak testing teams. - Results (to be) documented in WISH - Long clamshell tool has been developed and validated: to test 2 M welds simultaneously, to pump and backfill the 214 m He volume at a predefined unwelded M sleeve, to bridge a splice NC (if left unwelded). - Standard clamshells also available (M, SSS diode). - First subsector – 16 interconnects - released for vacuum test yesterday (22/7/2013) Paul Cruikshank TE/VSC - Leak Test QC of Cold vacuum Systems - 4 th Splice Review, 23/7/2013 13

Phase 2 - Leak test support to SIT - Leak testing team attached to SIT production, - Weekly meeting to review past week, next week, any issues, - Test tooling operational - optimisation is continuous process (VSC & MSC)…. . - Results documented on VSC/EIV sharepoint page. Paul Cruikshank TE/VSC - Leak Test QC of Cold vacuum Systems - 4 th Splice Review, 23/7/2013 14

Phase 2 - Leak test support to DFBA - Leak testing team available for DFBA production, - Test tooling optimisation is continuous process (VSC & CRG)…. . - Results documented on DFBA site & VSC/EIV sharepoint page. Paul Cruikshank TE/VSC - Leak Test QC of Cold vacuum Systems - 4 th Splice Review, 23/7/2013 15

Phase 2 - Leak test support to DN 200 - Leak testing on call for DN 200 production, - Baseline is to make sample intermediate testing to check process (100% phase 3 test) Start of production (~35 made at S 78 start) Change of weld parameters/procedure (~ 8 made), Series (5%) - Results documented in Wi. SH & VSC/EIV sharepoint page. DN 200 weld leak (1 E-1 mbarl/s) Adjacent to QQBI. A 29 R 8 Paul Cruikshank TE/VSC - Leak Test QC of Cold vacuum Systems - 4 th Splice Review, 23/7/2013 16

Phase 2 – oil & MLI observations Sector 8 -1 (A 11 L 1. M & A 15 L 1. M) & 2 -3 (A 11 R 2. M), Oil traces at several interconnects, accompagnied with MLI debris Q 26 L 6 - oil in cryostat On-going checks: TE-VSC confirms no abnormal insulation vacuum pressure in affected subsectors TE- CRG confirms no abnormal heat loads in affected subsectors. Oil composition analysis on-going – primary pump oil? Origin of oil? Incident during LHC installation tests, eg mobile pump malfunction? Incident during LHC cold operation eg negative pressure gradient cryostat to fixed pump? MLI debris? May come from fast venting/vacuum break – when ? Connection between oil & MLI debris not (yet) understood. Paul Cruikshank TE/VSC - Leak Test QC of Cold vacuum Systems - 4 th Splice Review, 23/7/2013 17

Results so far…. . Leak Test summary: Phase 1: He to BV – no problems Air to IV – several NC to solve He to IV cryomagnets – 20 confirmed existing leaks, 14 localised for repair He to IV QRL - 7 confirmed compensator leaks, repair on-going Phase 2: SIT, DFBA, DN 200 – ok, on-going M welds Paul Cruikshank TE/VSC – just starting…. - Leak Test QC of Cold vacuum Systems - 4 th Splice Review, 23/7/2013 18