TCC2/TDC2 Shutdown Activities and Consolidation Plans

1. TCC2/TDC2 Shutdown Activities and Consolidation Plans On behalf of the TDC2/TCC2 WG team http://cern.ch/tcc2tdc2WG IEFC Workshop, March 08, 2012

2. Agenda • Planned works for TAX repair • Other shutdown activities in the cavern: targets, magnets, infrastructure improvements • List of activities for LS1 in view of operation in 2014

3. Repair and review the North Area TAXs • TAX motor failure • The TAXs, installed downstream of the primary targets of the North Area, are made of massive blocks put on motorized tables that can move up/down. • High radiation environment • The TAX blocks intercept about 1019 protons/year about 6 mSv/h outside the shielding and probably 30 to 40 mSv/h at the blocks and evenhighernear the beam impact point

4. H2 TT20 T2 H4 H6 H8 T4 P0 T6 M2 Repair of the North Area TAXs: Scope of work • XTAX Repair • 8 out of 12 TAX tables to be repaired in the 2011/2012 shutdown • T2, T4 TAXs : avoid compromises to physics program as in 2011 • T6 TAXs : present situation has no impact to physics of COMPASS • T6 TAXs to be repaired in LS1 • Adopted solution • replace existing motors with spare ones • motors showed a rather long lifetime (10 years) • they are as RADHARD as we can presently get • search for new ones ongoing but longer delays • maintain existing location underneath the TAX blocks • investigated other options but rejected due to space limitations • optimize exchange procedure • for motor itself but also for the area in general • fully remote exchange using robotic manipulators under investigation

5. Repair of the North Area TAXs: scenario Access for greasing screw S. Girod EN-MEF Telescopic spring

6. Repair of the North Area TAXs: WDP & DIMR • A detailed repair procedure and a risk analysis are prepared • Major remaining risk: PR537 reliability Technical measurestaken: extensive maintenance and spare parts • Optimization steps WDP and DIMR preparation DIMR link • Design Review: reduce the dose in future interventions • Handle TAX assembly (blocks + table) as a set: no access to most activated part • PR537 remote control: reduced presence in TCC2 • Increase PR537 lifting height: lateral shielding stays in place • Bunker for mechanical work: operators well shielded • Tailor made shielding (100 mm thick steel plate + lead 50mm): dose reduction /80 • Optimize table repair sequence: # movements, start with least activated first • Extensive dry run tests in EHN1: train technicians • Extensive dry run tests in TCC2 : train crane operators

7. Repair of the North Area TAXs: dry run tests • Check and validation of: • Work breakdown • Time estimate & allocated resources • Tooling • Training sessions were organized for each stakeholder

8. Repair of the North Area TAXs: DIMR detail Work breakdown & planning Dose estimate Riskanalysis Personnel involved, statistics

9. Repair of the North Area TAXs: Work Dose Planning • Collective dose: 8.4mSv, • 36 people involved, • max individual dose: 436 uSv Collective dose (uSv) Individual dose (uSv) M1: mechanics (8) M2: mechanicsexpert (8) T: transport (6) RP: Radiation protection team (4) S: survey (2)

10. Repair of the North Area TAXs: Work Dose Planning Work near the hot elements Reminder TAX renewal in 2002: collective dose 23,9 mSv, Max individual dose 4.2 mSv

11. Repair of the North Area TAXs: Work Dose Planning

12. Other Shutdown activities: overhead crane upgrade • Overhead crane PR532 built in 1976 • Logbook  not frequently used (2001-2003: XTAX, 2006: Shielding, 2011: Lighting renewal) • Failure modes investigated (experiences from ECN3 crane, same generation)  speed variators are the weak link. • Thorough preventive maintenance and load tests including motor electrical isolation measurements and cable connection check. • 3 speed variators were sent to and inspected by the supplier. • Auxiliary motors are available in case of motor failure • No embedded electronics (located in electrical cabinets in safe area TA801) • A remote handling controller is now installed and new lifting jigs are available • Intensive crane training with dummy load in TCC2 is ongoing

13. Other shutdown activities: TCC2 Targets • Review of failure modes and of the procedures to recover from each failure. • Mobile shielding motor failure is the most important failure mode. • Identification of necessary urgent consolidation actions to be done during the 2011/2012 winter stop. • Mobile shielding motor replacement test and annual target stations maintenance • Review of the design and proposal of eventual modifications during LS1 • Redesign based on the same principles: no major change but replacement of existing and aged equipment with new generation items • Preparation of ALARA meetings for clearly identified procedures. • Done for mobile shielding motor replacement • To be done for LS1 activities

14. Other shutdown activities: Vacuum repairs High radioactivity + high relative humidity + PVC (Cl) ↓ Corrosions of stainless steel elements and deterioration of polymeric gaskets (valves’ mechanism) ↓ Vacuum leaks and frequent interventions • General survey of the vacuum system • Visual inspection of all vacuum chambers and bellows • Protect the existing vacuum chambers from falling acid droplets with Kaptonfoil • Removal of Al foils (not suited for acid protection) • Chambers and splitters are covered by Kapton foils that are tighten by stainless steel wire • Detect and repair as soon as possible suspected leak • Leak found onthe end window of sector 2020, new windows under construction, will be replaced in week 12 • Replacement of two sector valves

15. Other shutdown activities: Beam line maintenance • Beamlines inspection & maintenance • Collimator XCHV058 and XCHV070 exchange • Vacuum leaksearch and fix (sectorfollowing TAX6 up to QWL080) • Protective caps installation on 3 XCSV collimators (H2 and H4 lines) beam

16. Other shutdown activities: Magnet, Cooling and ventilation, Survey • Magnets • Magnet patrol carried out last Friday (02/03) • 3 Magnets to be shimmed • 1 magnet to be replaced (QNL) • Will be completed in the coming weeks • Cooling and ventilation • AHU’s maintenance completed • Inspection of water circuit valves in view of replacement of faulty ones in LS1 • Laser scanning TDC2 and TCC2 • Will allow integration and 3D modelling works in view of LS1 • Directly readable via TRUVIEW • Reduceneed of visit on site  ALARA

17. List of activities for LS1: TCC2 Targets Target Box BAC TBIU Monitor TBID Monitor Mobile shielding motor Switchs Budget & resources OK for consolidation during LS1 Patch Panel Fan Courtesy of D. Grenier (EN-STI)

18. List of activities for LS1: Cabling campaign • Replace irradiated cables, avoid unnecessary cable length if possible, eliminate cable with PVC if possible • Cable campaign foreseen end 2013 for 4 months • Only signal and control cables (not DC cables) between patch RAL and Patch RX • 700 cables = 100 km in TCC2/TDC2 for the time being • End user to fill a DIC if additionnal request Budget & resources OK for consolidation during LS1 TCT: Top cable tray, AA: Almost All, R: Rest, Part: Partial.

19. List of activities for LS1: Air handling unit and cooling circuit • Leaking valve replacement foreseen in LS1 • North Area AHU consolidation planned for 2017 and cooling station for 2021 • Should be re-considered in order to solve beam pipe stress corrosion issue (add humidity control, make controls reliable) • Increase efficiency of air ventilation: at present the TDC2 tunnel is a dead-end and no clear air flow is set in the extremity toward TT20. No budget nor resources for consolidation during LS1

20. List of activities for LS1: Magnet refurbishment • New cooling connection for all magnets • Global replacement of EPDM/Kevlar water hoses and gaskets in TDC2 / TCC2 • Interlock: Thermometer and Manometer contacts get corroded, triggering inconsistent machine stops; • Insulation of cables is cracked in the patch panels, the magnet safety system could malfunction • Interlock systems will need consolidation in the future. A more modern system should be defined and implemented at the same time. No budget nor resources for consolidation during LS1

21. List of activities for LS1: Other activities • Vacuum beam pipe consolidation: Budget and resources TBC • Replace damaged vacuum chambers and bellows , add new ion pumps • T6 XTAX repair • Overhead crane PR537 revamping: only possible during LS2 • General infrastructure consolidation • Maintain drain network • Lights upgrade (rad hard lights to be developed)