HC Safety aspect Before cool down Cool down
HC: Safety aspect • Before cool down • Cool down • Powering test 18/10/2007 M. Solfaroli 1
Before cool down ACTIVITIES RISKS • Pressure test • Cryo valves reconfiguration • Leak test (with pressure) • Consolidation Pressure • ELQA_TP 4 A Electrical • Purging and Flushing He+Pressure • ELQA_TP 4 B Electrical 18/10/2007 M. Solfaroli 2
Before cool down: Pressure test • High pressure in the CRYO lines • During the week-end • Access forbidden to all the areas involved • Engineering Specification for each sector 18/10/2007 M. Solfaroli 3
Removal of mechanical blocking of: Before cool down: CRYO valves reconfiguration • PV 930 and CV 930 between the QRL and the DFBs (normally closed) • CV 920 between line C and Cold Mass (normally closed but forced open during the pressure tests) NO INTERFERENCES In the shade of leak tests (with pressure) P t Changing of the poppets of the CV 910 (before QUI) This activity must be done only as soon as all lines have been depressurized (consolidation) 18/10/2007 M. Solfaroli 4
Before cool down: leak tests and consolidation DURING THIS PERIOD: • The lines can be pressurized and depressurized on a frequent basis • Somebody can be touching a cryogenic circuits t NO WORKS ON: • any line (B, C, D, E, F) • QUI • cryogenic part of DFBs Main actors: VAC+MCS helped by ACR 18/10/2007 P M. Solfaroli 5
WHAT AND WHEN Before cool down: El. QA TP 4 A • 4 electrical tests on circuits (1 with HT) • Normally 1 week • Everything is grounded NO WORK ON: • QHPS • PCs (60 A included) • DFBs BALISAGE • DFBs areas fenced off by El. QA team • PCs areas to be fenced off LHC-DE-TP-0007 -00 -10 “ELQA QUALIFICATION OF THE SUPERCONDUCTING CIRCUITS DURING HARDWARE COMMISSIONING” EDMS n. 788197 18/10/2007 M. Solfaroli See also Davide’s slides… 6
Before cool down: Purging and Flushing SITUATION • Interconnection closed • Cryogenic circuits closed • DO NOT OPEN ANYTHING Possible interferences with cryo activities 18/10/2007 M. Solfaroli 7
WHAT AND WHEN Before cool down: El. QA TP 4 B • normally 2 days • HT (up to 1. 9 k. V) • Everything is grounded NO WORK ON: • QHPS • PCs (60 A included) • DFBs BALISAGE • Access to all sector restricted • PCs areas fenced off by HCC • DFBs side fenced off by El. QA team LHC-DE-TP-0007 -00 -10 “ELQA QUALIFICATION OF THE SUPERCONDUCTING CIRCUITS DURING HARDWARE COMMISSIONING” EDMS n. 788197 18/10/2007 M. Solfaroli See also Davide’s slides… 8
HC: Safety aspect • Before cool down • Cool down • Powering test 18/10/2007 M. Solfaroli 9
ACCESS 300 K 80 K Cool down • Access allowed only to CRYO operators • Access managed by AT/ACR 80 K 1. 9 K • Access restricted • Access managed by HCC • All the intervention MUST be coordinated and approved by HCC 18/10/2007 M. Solfaroli 10
HC: Safety aspect • Before cool down • Cool down • Powering test 18/10/2007 M. Solfaroli 11
• Organization of the HC team Powering tests • Roles • Responsibilities See Roberto’s slides… • Management of safety • Access to the underground • Interference between incompatible activities • Tracking and informing about the activities 18/10/2007 M. Solfaroli 12
Powering tests: safety – access to the underground areas Personal authorisation using personal CERN access card, after having requested through EDH the “LHC Hardware Commissioning (LHC-HC)” access zone authorisation. Special temporary authorisation, using special access cards distributed by the Engineer in charge (EIC). These cards must be brought back to the EIC once the intervention is completed. Access key Blue chip token Engineering specification LHC-S-ES-0018 rev 0. 2 “ACCESS PROCEDURES FOR THE LHC TUNNEL AND THE RELATED UNDERGROUND AREAS DURING POWERING TESTS AND ELQA AT COLD” EDMS n. 857641 18/10/2007 M. Solfaroli 13
Powering tests: safety – Interaction between incompatible activities CONSTRAINTS: • Access to the Uas restricted during all the period of powering; • Access to the tunnel controlled by HCC during all the period of powering; • Access to a powering subsector forbidden when a main circuit is powered above 1 k. A or the QH are being discharged; • Access forbidden around the QHPS during IST of the QPS; • No access to a DFB even when only one circuits located on it is being powered (balise area); • Access restricted around the switches of the EE system when a main circuit is being powered at high level current (noise protection). 18/10/2007 M. Solfaroli 14
Powering tests: safety – Tracking and informing about activities morning shift afternoon shift 7. 00 15. 00 16. 30 22. 00 8. 30 PTC Point Owner EIC All the activities MUST be announced! 18/10/2007 M. Solfaroli 15
Powering tests: safety – Tracking and informing about activities http: //p 2 n. web. cern. ch/p 2 n/ 18/10/2007 M. Solfaroli 16
Powering tests: safety – Tracking and informing about activities What has been already done 18/10/2007 M. Solfaroli 17
Powering tests: safety – Tracking and informing about activities What is happening now 18/10/2007 M. Solfaroli 18
Powering tests: safety – Tracking and informing about activities War Map TEAMS 18/10/2007 Cryo/DFBs Light blue CL team Green El. QA team Yellow QPS team Blue EE Red PCs team Black RF team White M. Solfaroli 19
Conclusions Good coordination is crucial to avoid incidents All the activities in the field must be announced and reported See Roberto’s slides… 18/10/2007 M. Solfaroli 20
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