What are today s issues for all other magnets

What are today's issues for all other magnets? AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 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? 1

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

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

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

Performance and Fault Scenarios AT-MEL è 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 (6 l/min instead of 4 l/min) to reach the requested ultimate performance. AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 è 2) No impact on energy during commissioning. è 3) Repair in situ for small damages / faults in short interventions. Replacement of magnet in all other cases. è 4) Number of spares barely sufficient. è 5) Magnet workshop exists, Main workshop delivers bits and pieces. è 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 5

Caveat (1) AT-MEL è Delays for exchange and repair will probably depend rather on radiation cool- AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 down times. Cool-down times depend on the length of intervention. For a MQW exchange >1 week è 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. è Magnet transport will be hindered by shielding blocks that will have to be removed. In particular in IR 7, 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 cooldown it can take place. è 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. 6

AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 Caveat (2) AT-MEL è 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. è 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. ) 7

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

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

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

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

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

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

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

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

Realistic Margin for the Inner Triplet AT-MEL è Using Lucas parameterization and ignoring the cooling (i. e. short times) AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 è Energy Density to reach Tcs in J/m^3 in the MPZ MQXA MQXB 2 m. J/cm^3, 0. 4 m. W/cm^3 16

AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 Summary of D 2 -D 4 Quench Training AT-MEL 17

MQM, MQY, MQXA, MQXB, MBX, MBRB, MBRS AT-MEL è 2) No impact on safe energy during commissioning AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 è 3 a) MQXA, MQXB, MBX, MBRB, MBRS: Replace with the one spare (warm-up, exchange, cooldown ~6 weeks) , repair magnet (6 months or more) è 3 b) 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 è Magnet building workshop needed in 181, Main workshop has to provide welders. è Cryostating must also be available. 18

AT-MEL Corrector Types è Main dipoles – 2464 Sextupole Spool Correctors MCS (100) – 1232 Decapole-Octupole Spool Correctors MCDO (100) AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 è 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) 4659 Corrector Magnets – 16 Sextupole-Dipole Correctors MSCB (see above) – 122 Dipole Correctors MCBC/Y (14) 13 Main types – 60 Long Trim Quadrupoles MQTL (4) 10 Contracts Inner Triplets è Insertion quadrupoles è – 27 Inner Triplet Dipole Correctors MCBX (3) – 9 Sextupole-Dodecapole Inserts MCSTX (1) – Total value of the spare correctors > 2. 6 MCHF 9 Inner Triplet Corrector Packages MQSXA => MQSX/MCSOX (1) 19

AT-MEL-MC Histogram for MCDs - India 300 250 100 50 M or e 9 8 7 6 5 4 3 0 2 Also the number of quenches to reach maximum +2 is considerably lower! 200 1 All Indian magnets reached design with the first quench. Number of magnets AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 MCD Number of quenches to reach 800 A 20

AT-MEL Histogram for MCOs - India AT-MEL-MC 450 400 350 All Indian MCO reach 100 A with one quench. In most cases one quench is sufficient to reach 160 A Number of magnets AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 MCO 300 250 200 150 100 50 0 1 2 3 4 5 6 7 8 More Number of quenches to reach 150 A 21

MCS Antec and CAT AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 550 A AT-MEL 850 A Including one extra quench 22

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

AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 MQTs 550 A 600 A The MQT family has a comparatively high field and gradient, I don’t expect much better behavior at 1. 9 K 24

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

AT-MEL Inner Triplet Correctors AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 Q 3 M C S O X M C B X A MQXA Q 2 M Q S X B P M MQXB LMQXC LMQXB B 4 A 3 A 1 / B 1 B 6 / B 3 M C B X A 2 A 1 / B 1 Q 1 MQXB M C MQX B A X B P M LMQXA A 1 / B 1 To IP MCBX FNAL supplied KEK supplied CERN supplied 26

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

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

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

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

Summary AT-MEL è Warm magnets – Spares available, Manpower not available – Workshop as for all other warm magnets AT-MEL, K. H. Mess, “Chamonix” 2005, CERN, 1211 Geneva 23 è DS & MS – Modules as spares, must be configured to cold masses and cryostated. Workshop in 181 (press) necessary including manpower! è 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! è 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) 31