1. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 1 What are today's issues for all other magnets? Questions 1.) What are the as build performances of the other magnets vs. ones expected from the design? 2.) Any impact on the expected safe machine collision energy for commissioning? 3.) What is the repair/replacement strategy in case of a damage to a magnet? What are the delays? 4.) How many spares are foreseen? 5.) What can be expected from central workshop in case of problems? How long will it take?

2. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 2 What are “all other magnets” ?  Warm magnets –19 types, 845 items installed  Cold Dispersion Suppressor Magnets –5 types, made by combining 7 different types of magnets, 64 sets installed  Cold Matching Section –9 types, made by combining 7 different types of magnets, 50 sets installed  Cold Separation Dipoles –4 types, 20 installed (4 spares)  Inner Triplet Magnets –3 types, made using 12 different magnets, 8*3 sets installed (1 spare each)  Cold Correctors –26 types*), 4662 sets installed  In total 5669 magnets coming in 66 types (11h talk?) –*) depends on the way of counting

3. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 3 Warm Magnets in the LHC and the transfer lines

4. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 4 Septa and Total Sum of Warm Magnets

5. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 5 Performance and Fault Scenarios  1) 'As built' performance of all magnets is higher or equal to the one expected from the design. MBXWT will require a higher water flow-rate (6l/min instead of 4l/min) to reach the requested ultimate performance.  2) No impact on energy during commissioning.  3) Repair in situ for small damages / faults in short interventions. Replacement of magnet in all other cases.  4) Number of spares barely sufficient.  5) Magnet workshop exists, Main workshop delivers bits and pieces.  Anticipated Faults: –Leakage due to Corrosion, Erosion, Mechanical forces on connectors –Blocking of cooling circuit- Thermo-switch fault –Insulation damage due to radiation, heat, forces –Beam damage- Transport accident

6. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 6 Caveat (1)  Delays for exchange and repair will probably depend rather on radiation cool- down times. Cool-down times depend on the length of intervention. For a MQW exchange >1week  The minimum replacement time depends on the time needed to bring the transport vehicles in the right places and to prepare them for the specific magnet type. At least one day, better two should be foreseen for this operation.  Magnet transport will be hindered by shielding blocks that will have to be removed. In particular in IR7, it is unclear to me, how and how far they are to be transported, what the impact of this operation is and at what moment of cool- down it can take place.  Repairs of the magnet connections can be executed after cool-down of the magnet. Exchange of coils requires opening of the magnet with particular tools. We have so far recuperated tools from the manufacturers or requested to keep them in a good shape for us and we will do so in future.

7. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 7 Caveat (2)  Handling equipment for Russian magnets is not CE certified and will therefore not be readily accepted by SC. Currently no workunits for the repair, adaptation or replacement-acquisition of such equipment is forseen. It will require considerable time and effort to do such repairs. However, the time needed should be guaranteed by a sufficient number of spares.  MQW in particular is a structurally sensitive magnet that requires a particular procedure with sufficient space and time. As far as possible, the detailed production procedures were collected and filed. However like in football, it needs time to replace a trained team that achieved the tasks on a series of 52 magnets. (E.g. we know that the multipole parameters over the series follows a clear trend.)

8. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 8 Optimistic Magnet Exchange Schedule In total 22 man hours, in about 7hours. Preparation, Vacuum and Alignment not counted

9. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 9 Optimistic Magnet Exchange Schedule In total 22 man hours, in about 7hours. Preparation, Vacuum and Alignment not counted 17 man hours work for MEL The section has only 12+1 staff and 10 industrial support for all accelerators The LHC subsection (knowledge of the MQW) has 3 staff +1 industrial support The radiation dose/magnet exchange is estimated to ~19 mSv, thereof ~12 mSv for MEL. To stay below 2mSv/man/intervention => 6 people needed to exchange 1 magnet/month and 5/year.

10. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 10 Optimistic Magnet Exchange Schedule In total 22 man hours, in about 7hours. Preparation, Vacuum and Alignment not counted 17 man hours work for MEL The section has only 12+1 staff and 10 industrial support for all accelerators The LHC subsection (knowledge of the MWQ) has 3 staff +1 industrial support The radiation dose/magnet exchange is estimated to ~19 mSv, thereof ~12 mSv for MEL. To stay below 2mSv/man/intervention => 6 people needed to exchange 1 magnet/month and 5/year. MEL would be unable to exchange a MQW under the present conditions

11. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 11 Quench Behaviour of MQM and MQY Magnets in the Matching Section and Dispersion Supressor MQM MQY Extraordinary good quench behavior Quench margin 1mJ/cm^3 in DS and 5mJ/cm^3 in MS (short disturbance)

12. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 12 Summary of MQXA Quench Training, Inner Triplet Number of quench reduced Number of quenches high due to fault in the bore.

13. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 13 Summary of MQXA Quench Training, Inner Triplet Number of quench reduced Number of quenches high due to fault in the bore. 225 T/m

14. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 14 Summary of MQXB Quench Training, Inner Triplet Short sample current

15. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 15 Summary of MQXB Quench Training, Inner Triplet 225 T/m

16. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 16 Realistic Margin for the Inner Triplet  Using Lucas parameterization and ignoring the cooling (i.e. short times)  Energy Density to reach Tcs in J/m^3 in the MPZ MQXA MQXB 2 mJ/cm^3, 0.4 mW/cm^3

17. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 17 Summary of D2-D4 Quench Training

18. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 18 MQM, MQY, MQXA, MQXB, MBX, MBRB, MBRS  2) No impact on safe energy during commissioning  3a) MQXA, MQXB, MBX, MBRB, MBRS: Replace with the one spare (warm-up, exchange, cooldown ~6 weeks), repair magnet (6 months or more)  3b) MQM, MQY, MQTL: No complete spares available due to the big number of different combinations. At least two month for building a new assembly, followed by test, installation, ELQA, cool down, ELQA ~1 month  Magnet building workshop needed in 181, Main workshop has to provide welders.  Cryostating must also be available.

19. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 19 Corrector Types  Main dipoles –2464 Sextupole Spool Correctors MCS(100) –1232 Decapole-Octupole Spool Correctors MCDO (100)  Main quadrupoles (Short Straight Sections) – 360 Sextupole-Dipole Correctors MSCB (20) – 192 Tuning and Skew Quadrupoles MQT/S (20) – 168 Octupole Lattice Correctors MO (20)  Insertion quadrupoles – 16 Sextupole-Dipole Correctors MSCB (see above) – 122 Dipole Correctors MCBC/Y (14) – 60 Long Trim Quadrupoles MQTL (4)  Inner Triplets – 27 Inner Triplet Dipole Correctors MCBX (3) – 9 Sextupole-Dodecapole Inserts MCSTX (1) – 9 Inner Triplet Corrector Packages MQSXA => MQSX/MCSOX (1) 4659 Corrector Magnets 13 Main types 10 Contracts Total value of the spare correctors > 2.6 MCHF

20. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 20 MCD All Indian magnets reached design with the first quench. Also the number of quenches to reach maximum +2 is considerably lower! Histogram for MCDs - India 0 50 100 150 200 250 300 123456789 More Number of quenches to reach 800 A Number of magnets AT-MEL-MC

21. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 21 MCO All Indian MCO reach 100 A with one quench. In most cases one quench is sufficient to reach 160A Histogram for MCOs - India 0 50 100 150 200 250 300 350 400 450 12345678More Number of quenches to reach 150 A Number of magnets AT-MEL-MC

22. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 22 MCS Antec and CAT 550 A850 A Including one extra quench

23. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 23 MOs 255 MOs reach the nominal current (550 A) at the first quench, 5 MOs at the second quench 700 A

24. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 24 MQTs The MQT family has a comparatively high field and gradient, I don’t expect much better behavior at 1.9 K 550 A600 A

25. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 25 Margin of the Q6 in IR3 (6 MQTLs) Energy [J/m^3] needed to raise the temperature from 4.3 K to Tcs, cooling ignored ~in Gray if divided by 10^4 10 mJ/cm^3 Looks better than I expected 1 mW/cm^3

26. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 26 Inner Triplet Correctors KEK supplied CERN supplied MQXB MQX A MCBXMCBX MCBXMCBX BPMBPM BPMBPM LMQXC LMQXA To IP  Q2Q1 FNAL supplied A1 / B1 MQXA MCBXAMCBXA MQSXMQSX LMQXB MCSOXMCSOX Q3 A1 / B1 B6 / B3 B4 A4 A3 A2 MCBX

27. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 27 Quench performance: MCBX #4 Individual powering Courtesy of AT-MTM

28. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 28 Superconducting motor MCBX: Combined powering

29. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 29 MSCB: Quench Performance Production “fault” was intercepted, newer magnets are much better Sextupoles are quenching much better as well.

30. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 30 MSCB: Quench Performance

31. AT-MEL AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 31 Summary  Warm magnets –Spares available, Manpower not available –Workshop as for all other warm magnets  DS & MS –Modules as spares, must be configured to cold masses and cryostated. Workshop in 181 (press) necessary including manpower!  Inner Triplett and Separation Dipoles –½ insertion as spare. –Repair situation unclear to me (Japan/Toshiba- US/BNL/FNAL) –Expected to fail within 7 years, we must start a replacement design now!  Correctors –Included in the other magnets –Spares available, manpower barely sufficient in the long run! –Repair in house (> ½ year or longer if wire has to be procured)