Pettersson, Thomas Sven

Rodríguez-Mateos, F

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SESSION 6 - EFFECTS OF THE COMPRESSED SCHEDULE ON THE INSTALLATION – SUMMARY  T. Pettersson, F. Rodriguez-Mateos, CERN, Geneva, Switzerland  Abstract This paper summarizes the session 6 presentations that discussed issues related to the installation process, schedule, hardware availabilities and machine descriptions. One presentation described the installation of the experimental insertions and the long straight sections dedicated to machine systems (LSS). The experimental LSS’s present special problems since the machine installation has to be synchronised with the installation of the experiments and any equipment delays on either side have major implications for both machine and the concerned experiment. A major issue for the installation is the magnet testing facility (SM18) and its nominal and real throughputs. The upgrade plans to reach the nominal rates for both dipoles and quadrupoles were presented. The hardware commissioning team faces a major task with the planned parallel activities; possible solutions and some outstanding problems were discussed. The LHC control system is a major component of this machine, an overview of the planned roadmap as well as already achieved milestones were given. INTRODUCTION In Session 6 issues directly related to the LHC installation and the commissioning of the LHC’s technical systems were discussed. The objective of the session was to give an as complete overview as possible of issues that affect the beam commissioning. The speakers presented their major concerns which range from scheduling problems, missing equipment information, tight synchronisation requirements with the LHC experiments to scarce resources for the hardware commissioning and magnet testing throughput rates. UPDATE ON LHC INSTALLATION SCHEDULE The principal questions this presentation addressed were related to the new schedule that still remains to be defined and the installation progress limitations due to logistics constraints. The global LHC installation schedule which is directly linked to the schedule of the installation of the cryogenic feed line, the QRL, is still not completely defined as CERN waits for a definite schedule from the contractor. However, a strategic objective to have colliding beams in the LHC in the summer 2007 has been set by the CERN management. As soon as the QRL schedule is defined the many different equipment groups will be consulted to permit the IC group to finalise the overall schedule. A major change in the scheduling process is that man-power resources are now to be considered without limits and that installation sequences have to be parallelized wherever possible, even to the extent that some equipment will only be commissioned in its final configuration: the QRL will not be completely commissioned in cold before the cryo-magnet assemblies are installed in front of it. The installation of the long straight sections pose a special problem as the installation of the machine elements have to be synchronised with the installation of the LHC experiments. For LSS8, with the LHCb experiment, the schedule is expected to be defined in February 2005 while for the reminder of the installations in sectors 78 and 81 the Schedule Change Requests (SCR) will be submitted for approval during the spring and early summer of 2005. Installation rates depend on the availability of tested and accepted magnets, the rate of the final preparations of each cryoassembly in the SMI2 facility and the shaft and tunnel transport capabilities.  The present dipole magnet manufacturing rates will make 1240 cold masses available in summer 2006. The currently achieved rate of magnet testing in SM18, 55 magnets/month will have to be increased, see also below, to 69 magnets/month to permit the closing of the machine in late 2006 or very early 2007. The logistics capabilities now available support a transport rate of 20 cryomagnets/week. If the magnet installation starts in March 2005 the last magnet will be transported into the tunnel and placed in its slot by December 2006 (~ 90 weeks).  The parallelisation of the installation is not only dependent on the availability of resources, certain activities preclude co-activities. Pressure tests and X-ray control of welds can not be done in parallel with transport or work sites in the immediate vicinity of the tests. Hence, careful scheduling of such tests will be required to minimise the time “lost”. Co-activities during cool-down are however expected to be possible according to an extensive risk analysis made earlier by the AT dept. The final schedule is expected to be available in the summer 2005. Hardware commissioning is planned to start in summer 2006 and is expected to end in June 2007. COMPRESSED SCHEDULE - THE LAYOUT POINT OF VIEW The LHC configuration database describes what equipment is installed and where it is installed in the 26 km long tunnel and in the caverns. Information from this database will be used in many application programs used to operate and maintain the machine. The layout database is not yet complete and some space conflicts still have to be solved. About 10% of the machine elements are still LHC Project Workshop - ’Chamonix XIV’18missing, amongst which can be mentioned beam instrumentation, vacuum chambers and access safety beam stoppers. The QRL and its supporting systems are not completely defined everywhere yet. One space conflict e.g. is located in IR5 and has to be resolved. The final version of the layout V6.501 will be ready for the spring 2005 and changes will be handled through the well tested ECR mechanism. INSTALLATION OF THE LONG STRAIGHT SECTIONS Four of the LHC long straight sections (Points 1, 2, 5, 8) are used by the experiments and the remaining four are used for machine services (Points 3&7 for beam cleaning, Point 4 for RF and Point 6 for the beam dump). The installations of the experimental LSS’s are critical and complex since the machine and the experiments are interdependent and have to be synchronised in detail to be possible. Sector 7-8 and the LHCb installation interaction give a good example of this issue. Another subject is the equipment readiness. Some operations have to be staged and are very difficult to delay or roll-back (LHCb and QRL installation for instance) in case of problems with missing equipment, see also Fig. 1.   Figure 1  QRL installation in Point 8  The provisional dates for the installation of the LSS are:  1. LSS8L ⇒  August 2005  2. LSS8R ⇒  October 2005  3. LSS1L ⇒  October 2005  4. LSS5L ⇒  December 2005  5. LSS5R ⇒  April 2006  6. LSS2L ⇒  July 2006  7. LSS1R ⇒  August 2006  8. LSS2R ⇒  September 2006   Each of the LSS is a particular case and will have to be handled differently due to the specific configuration of the area and its specific safety constraints. This imposes restriction on co-activities, on transports, on access during pressure tests, cool down and electrical tests. A formal Schedule Change Request (SCR) will be required for each LSS before the final planning is frozen. MAGNETS COLD TESTS AND THROUGHPUT The LHC magnets are cold tested in the SM18 complex which has twelve 12 test benches in operation in a 24/24 hour schedule. The presently achieved throughput rate, 55 magnets/month will permit the project to terminate the testing in March 2007, which is too late with respect to the strategic objective of having colliding beams in summer 2007. The required rate to terminate magnet testing in November 2006 is 65 magnets/month. To ensure that this rate is reached within the next few months a number of proposed hardware upgrades and other process improvements will be undertaken. Table 1 shows the production rates achieved during 2003 and 2004. To note is that 11% of the magnets have been retested for a number of reasons, thus occupying valuable bench space and time.  Table 1 – SM18 achieved production rates   Dipoles Dipoles repeated Arc-SSS Arc-SSS repeated  IR-SSS  2003  95  n.a.  2   n.a.  n.a.  2004  358  38 (~ 11%)  49  3  3  TOTAL  2004 396 Includes  Rejects & Repeats 55 Includes  Rejects & Repeats   Total cum.  491  57  HARDWARE COMMISSIONING (HWC) The hardware commissioning was initially, before the QRL delays occurred, planned to last 36 months. In the present scenario 12 months are made available. The hardware commissioning will start in June 2006 and end in June 2007. The HWC team has in its programme work concentrated on the commissioning of the superconducting electrical circuits. The planning of the commissioning of other accelerator subsystems will take place during the spring 2005. The final programme depends naturally on the detailed installation schedule which will only be available by summer 2005. F. DELSAUX 27/04/2004  RB86 Shielding QRL MBXWSLHC Project Workshop - ’Chamonix XIV’19Compressing the available time for commissioning is only possible if the activities are parallelized which implies that more resources, both human and material will be required since the total volume of work remains constant. Commissioning hardware as complex as the LHC requires both experienced personnel and experienced and trained supervisors. A major effort is now being made to have collaborations with major national and international laboratories to make such personnel available for the commissioning period. The present resource situation is not compatible with a 12 months commissioning period.  The HWC team also expects support from both the AB/CO group as well as other general CERN services. In particular the team expects to have a user friendly application program suite, programmed procedures for battery tests and tools to aid the interpretation of the test results. Extensive support from the MTF and database services will be required, in particular as concerns the optimization of the MTF configuration for hardware commissioning and exchange of data between the central database and the databases “owned” by various specialists.  The preparations of the programme, the scenario, the documentation, the tools and the infrastructure for the hardware commissioning are well in hand. It is planned to have the HWC readiness to be assessed by a review during the spring 2005 to ensure an objective view of all critical issues. The complete picture will however only be visible after a close-to-final installation schedule becomes available. In 2005 with the commissioning of the QRL subsector and cryomagnets left of Point 8 a first verification of the HWC programme assumptions will become available. This should give a solid indication of their real validity for the remainder of the commissioning work. CONTROLS The presentation started with a road map of the basic system functionalities that will be made available. One important milestone with beam has already been passed with success: the TI8 injection line. Next milestone, with beam is the commissioning of the ion accumulator – LEIR which has been completely refurbished. Target date for this milestone is spring 2005, see Fig. 2.  The LHC control system is a complex and large system. The managed volume of equipment and process data is large – configuration and data management issues will be of prime importance to maintain coherence. Naming conventions of process parameters, equipment and signals are defined and will have to be strictly adhered to if chaos is to be avoided. In Fig. 3 is shown schematically, by what milestone, a given basic facility of the control system has to be delivered by the controls group to the HWC and the Operations teams. In addition to the basic facilities of the control systems such as logging, alarms, database management tools, a large number of application programs have to be created. A complete list of these applications is however not yet available. The technical specifications for the these programs are expected by AB/CO to come principally from the user communities.   Figure 2  Main LHC Control system milestones   Figure 3  Basic control system tools availability CONCLUSIONS The detailed LHC installation schedule still has to be worked out – but the global milestones are defined, in particular the date for colliding beams. There is still equipment missing in the layout description database and this has to be completed as soon as possible. Changes to the configuration of the machine can be accepted using the ECR mechanism to ensure a coherent change management. The LSS integration issues are critical and time dependent – the requirements on the availability of machine equipment and the synchronization of the installation with the experiments LHC Project Workshop - ’Chamonix XIV’20create very complex situations for both parties. In some cases it is quasi impossible to accommodate  late equipment!  The hardware commissioning can be parallelized – if the required resources are made available, but the real minimum duration has still to be assessed (20 months or less…). A 1st dress rehearsal will be made when commissioning the sub-sectors to the left of Point 8 this year. For the LHC control system the basic infrastructure with a large number of important facilities is being put into place, and a series of important milestones have been defined; one was the TI8 injection test which was passed successfully, the next milestone is the LEIR commissioning. The required LHC application programs must now be defined and specified to permit the programming to start in order to be ready for the start-up of the machine in 2007. ACKNOWLEDGEMENTS Our thanks to the speakers of session 6: S. Weisz, S.Chemli, S. Bartolome, V.Chohan, R. Saban and R. Schmidt.  LHC Project Workshop - ’Chamonix XIV’21

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