1. LTC Extended days, 03 March’08 J.M. Jimenez, AT Vacuum Group LHC Vacuum commissioning J.M. Jimenez On behalf of AT-VAC

2. LTC Extended days, 03 March’08 J.M. Jimenez, AT Vacuum Group Main Topics Breakdown of tests foreseen in preparation for beam Equipment folder e.g. tests results, handling of non- conformities, performance below specs, machine as commissioned vs. machine as specified Issues for sectorized cold check-out in parallel to HWC Alarms, signals and SW available in CCC Piquet and experts availability

3. LTC Extended days, 03 March’08 J.M. Jimenez, AT Vacuum Group Description of LHC Vacuum Systems Introduction The LHC has 4 different Vacuum Systems belonging to two types of vacuum applications & technologies  Insulation Vacuum Systems Cryogenic line QRL Magnet Cryostats The main purpose of the insulation vacuums is to decrease the heat exchange between the cryogenic lines/fluids and the external envelope at ambient temperature (RT).  Beam Vacuum Systems Cold Beam Vacuum RT Beam Vacuum The main purpose of the beam vacuums is to ensure the required the beam lifetime and luminosity while decreasing the beam/gas scattering and therefore the background to the experimental regions and the induced radiation to the surrounding equipments As a general rule in the LHC, the two circulating beam vacuums are kept whenever possible completely independent. Exceptions can be found in the experimental regions and in the injection kickers in 5L2 and 5R8.

4. LTC Extended days, 03 March’08 J.M. Jimenez, AT Vacuum Group Description of LHC Vacuum Systems General Layout of LSS Attention…! Vacuum crew uses : Blue beam instead of Beam 1 and Red beam instead of Beam 2

5. LTC Extended days, 03 March’08 J.M. Jimenez, AT Vacuum Group Breakdown of tests foreseen in preparation for beam Vacuum instrumentation  Each chain e.g. sensor – cable - patch panel or controller - PLC - PVSS monitoring user interface is checked individually. Similar checks are made on the ion pumps.  Pirani gauges are calibrated individually in situ Interlocks  To cryogenic systems Software interlocks given by two gauges: Pirani for the low level (0.1 mbar) and Piezo for the high level (500 mbar) – checked with cryogenics before cool down start  To other beam equipment RF cavities, kickers, diluters… hardware interlocks are checked with equipment owners before they start the commissioning of their systems  Individual sector valve (see next slide)  Sector valve chain interlock to the BIC The sector valve chain is checked using simulators instead of the valves (can not be opened right now) and a BIC controller provided by AB/CO  In presence of a pressure interlock, the valves will only be closed when the beam dump signal is confirmed by the BIC interface  The action buttons for the sector valves in the PVSS monitoring user interface are inhibited in presence of beams  Do we extend that to VPIs and VGs?

6. LTC Extended days, 03 March’08 J.M. Jimenez, AT Vacuum Group Breakdown of tests foreseen in preparation for beam In the LHC, the cold beam vacuum sectors are always surrounded by RT beam vacuum sectors. But the RT beam vacuum sectors can have cold or RT beam vacuum sectors at their interfaces.  Sector Valve Closing A vacuum interlock generated by the ion pumps and Penning gauges located upstream and downstream of the sector valve (x) will fire the beam dump and then the sector valves (x), (x-1) and (x+1) will be closed. As a general rule, 3 or 4 signals are used to interlock the valve closure and the interlock will be triggered when n-1 signals are positive.  Sector Valve Opening The opening of a sector valve isolating a Cold / RT beam vacuum is allowed only if: The magnet is at his nominal temperature and the Penning of the Cold beam vacuum sector indicate pressures below 10 -7 mbar The Penning gauge of the RT beam vacuum indicate pressures below 10 -7 mbar and VPIs are all OK For an interface between two RT beam vacuums, the Penning gauges of both sectors shall indicate a pressure below 10 -7 mbar and VPIs are all OK

7. LTC Extended days, 03 March’08 J.M. Jimenez, AT Vacuum Group Breakdown of tests foreseen in preparation for beam Combined beams MKIs Case 1 Case 3 Case 2 Beam Vacuum Sector Valves Closure Green : Valve can be opened Red : An interlock is detected

8. LTC Extended days, 03 March’08 J.M. Jimenez, AT Vacuum Group Equipment folder Instrumentation  Tests results Reported in paper travelers  Non-conformities Repaired as soon as detected  Performance below specs Nothing identified yet Upgrade of the PVSS interface and PLCs software are made 4/5 times per year to adapt for new user requirements based on operation experience  Machine as commissioned vs. machine as specified Nothing identified yet

9. LTC Extended days, 03 March’08 J.M. Jimenez, AT Vacuum Group Equipment folder Vacuum chambers and components  Test results (vacuum acceptance tests) Chambers have been validated during the NEG deposition process – Tests and traceability reports are stored in MTF Warm interconnecting modules, BPMs, sector valve modules and gauges have been validated in bld113 test benches – Tests and traceability reports are stored in Nice LHC equipment manufactured by AB Department (except BPMs) have been validated in bld867 test benches - Tests and traceability reports are stored in Nice  Non-conformities during installation Non-conformities during vacuum acceptance tests are reported in the travelers stored in Nice Non-conformities during installation in the tunnel are reported in EDMS. Each non- conformance generates a non-conformity report which states the actions and induced limitations  Performance below specs Reporting depends on the stage at which they were detected e.g. test results or installation  Machine as commissioned vs. machine as specified See the template of the non-conformity reports

10. LTC Extended days, 03 March’08 J.M. Jimenez, AT Vacuum Group Equipment folder

11. LTC Extended days, 03 March’08 J.M. Jimenez, AT Vacuum Group Issues for sectorized cold check-out in parallel to HWC Instrumentation is checked prior to:  Starting the cool down: checking of the instrumentation of the arc magnets insulation vacuum and standalone magnet insulation vacuum  Starting of the bake out on the RT sectors: instrumentation on beam vacuum  These checks shall be completed in parallel with HWC Validation of valves  Final checking can only be made when the magnets are at cryogenic temperature  These activities will be made in parallel with HWC activities Tests during cold check out  Sector valves and sector valve chain shall be retested during cold check out

12. LTC Extended days, 03 March’08 J.M. Jimenez, AT Vacuum Group Alarms/signals/SW available in CCC Signals  Status of vacuum sectors, instrumentation, pumps… can be accessed using the PVSS software interface (see next slide)  This interface is installed in the CCC in the LHC and TI platforms and in cryogenic control rooms. Shortly, the vacuum pressure for the cryogenic sector will become available in the Control Middle Ware (CMW) for cryogenic crews  Vacuum OK signal for cryogenics is available in GTPM Alarms and signals  Alarms are not handled yet, discussion are on going with AB/CO and AB/OP to define which type of alarms shall be generated and how their shall be handle and “compressed”

13. LTC Extended days, 03 March’08 J.M. Jimenez, AT Vacuum Group Description of LHC Vacuum Systems Vacuum Supervision Interface QRL Insulation Vacuum Magnets Insulation Vacuum BLUE Beam or Beam 1 Beam Vacuum Sector Valve Chain* RED Beam or Beam 2 Beam Vacuum Sector Valve Chain* * Red = Valve(s) closed Green = all valves opened Blue = Control Problem or undefined position Interlock level on insulation vacuum Vac cryo OK 0.1 mbar alarm 500 mbar alarm

14. LTC Extended days, 03 March’08 J.M. Jimenez, AT Vacuum Group Description of LHC Vacuum Systems Vacuum Supervision Interface Beam vacuum TD68 dump vacuum TD62 dump vacuum Sector valve synoptic Detailed synoptic

15. LTC Extended days, 03 March’08 J.M. Jimenez, AT Vacuum Group Description of LHC Vacuum Systems Vacuum Supervision Interface QRL Vacuum Instrumentation Magnet Vacuum Instrumentation

16. LTC Extended days, 03 March’08 J.M. Jimenez, AT Vacuum Group Organization and duties of the Vacuum Piquet Support The operation of the vacuum systems of the running accelerators will rely on: A stand-by Piquet Service of 2 persons (rules for stand-by applies e.g. administrative circular N°27)  Stand-by starts on Wednesday at 9h and ends next Wednesdays at 9h (within the limit of 12 h/day and 57 h/week)  After being called by the CCC, the Piquet team has to identify the cause of the interlock and try to fix it. The duties of this first line is limited to the instrumentation, ion pumps and sector valve problems. Access to underground areas may be required  Other problems like controls failure and leaks… shall be addressed after taking advise with the experts. The experts shall be called by the vacuum Piquet via the CCC in order to register the intervention in the CCC logbook Vacuum experts (best effort, not in stand-by)  List of volunteers which are or not member of the stand-by service  The list of experts will only be communicated to the stand-by piquet  The expert volunteers will provide assistance to the stand-by piquet on a best effort basis. They will be called via the CCC in order to register the intervention in the logbook. The administrative circular N°27 applies for the overtimes and interventions  The expert, if available, could help to solve the problem by phone or could decide to intervene together with the stand-by piquet service

17. LTC Extended days, 03 March’08 J.M. Jimenez, AT Vacuum Group Organization and duties of the Vacuum Piquet Support Why using this new organization of Vacuum support for the running accelerators?  Stand-by piquet service will be able to solve about 90% of the problems Gauge is off and generates an interlock to the cryogenics or to sector valves Gauge controller is failing  restart or exchange Sector valve is blocked or is giving an undefined position  launch an open or close command, check the valve controller and reset it if required, increase the pressure using the pressure reducer  Experts (volunteers on best effort) helping the Stand-by piquet team Experts will provide an assistance to the Stand-by team and therefore will avoid stresses during the interventions Intervention on the LHC insulation vacuum e.g. exchange of a faulty turbo or installation of additional pumping Leak detection using Argon or using a leak detector  varnishing Leak repair when a venting of the sector is required PLC related problems (by pass of the interlocks could be required)

18. LTC Extended days, 03 March’08 J.M. Jimenez, AT Vacuum Group Organization and duties of the Vacuum Piquet Support