LHC Magnets: Cold Tests & Throughput
V. ChohanSM 18 Operation
CERN
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
2
Talk Outline
• The Environment– SM18 Operation – Boundary Conditions
• Current Situation– Results to Date – Summary
• Outlook– Projections – Concerns & Worries
(No Elaborate Status Report & Facts from the floor level !!!)
The Environment
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
4
SM18 Magnet Tests : What it’s all about
Demands on SM18 Operation
ProjectManagement
MagnetProduction
LHC Beam Running in &Minimum dI, dE
provision
AcceleratorPhysicists
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
5
Work Environment
• Fixed
• 12 Test Benches arranged in pairs so, 6 clusters( A to F)• 6 Main Power Converters • 6 sets of Electronics for testing 1 per cluster
• Mobile• For Q-location & MM we need to install Special 15 m Shafts• Shafts require Anticryostat mounting in magnets • Mobile Racks for HV insulation tests & Magnetic Measurements
• Utilities• Water for 4 magnet powering at the same time • Cryogenics capacity and limits
• Manpower [24 hr Tests Operation Staff special arrangements]• 7 CERN staff (up to end 2004) on loan from CERN Accelerator Operation• 15-20 persons on exact 1 year contracts from India & constantly rotating• Cryogenic Support staff ( 3 per shift) from Industrial Support contract • ICS “Magnet connectors” working 24 hours since June 2004, but not ROCLA operators
• SupportGeneralized Equipment support as opposed to specialized support as found in 24 Hr. OPERATION in CERN & “physics” is not at stake if specialist ‘fixing’ is delayed
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
6
Utilities : Cryogenics Capacity• Cryogenics capacity (in 2004) and limits :
3 to 5 Magnets @ 1.9K and under cold tests,
1 magnet in 300K to 90 K phase ,
1 magnet in Last (Warm up) Quench to 300K phase,
1 magnet in 90K to 1.9 K phase
with a further capacity constraint of not exceeding 9 recoveries of high field quenches or initial cooling from 4.2 K to 1.9 K per 24 h
We need to ensure that the magnets under the tests programme follow the cryogenic phase distribution as above, within the limits of possibilities due to the varying training performance ( a priori not known)
and respecting all the other environment constraints mentioned earlier
Current Situation
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
8
Magnets Tested: 2004
• A total of 396 Dipole & 55 SSS magnets were tested during the year 2004, these also include repeat magnets & IR-SSS.
• An estimate of 45 Dipole & 10 SSS magnets per month could be expected during year 2005, with the present environmental / test conditions
1
24
37 36
30
37 37
4341
47 48
15
05
1015202530354045505560
Num
ber o
f mag
nets
Tes
ted
Jan-04 Feb-04 M ar-04 Apr-04 M ay-04 Jun-04 Jul-04 Aug-04 Sep-04 Oct-04 Nov-04 Dec-04
Month
Cold Tests in SM18 in 2004
Total Dipoles
2
1
2
1
3
67 7
11 11
4
0
2
4
6
8
10
12
14
Num
ber o
f mag
nets
Tes
ted
Jan-04 Feb-04 M ar-04 Apr-04 M ay-04 Jun-04 Jul-04 Aug-04 Sep-04 Oct-04 Nov-04 Dec-04
Month
Cold Tests in SM18 in 2004
TotalSSS
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
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Results to Date
Dipoles Dipoles Repeated
Arc-SSS Arc-SSS Repeate
d
IR-SSS
Year 2003 95 Not Applicable
2 Not Applicable
Not Applicable
Year 2004 358 38(about 11%)
49 3 3
TOTAL 2004 396Includes Rejects & Repeats
55Includes Rejects & Repeats
Cumulativ
e Total 491 57
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
10
Cumulative Total: All Magnets
(including Repeats & Rejects)
Cumulative Cold Tested Magnets
821
95 96120
157
193
223
260
297
340
381
428
476491
2 2 4 5 7 8 11 17 24 3142
53 57
0
100
200
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600
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-02
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2
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-02
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v-02
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-03
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3
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v-03
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4
Sep
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No
v-04
Jan
-05
Month
Mag
net
s (
Rep
eats
+ T
h.
Cyc
l in
clu
ded
)
DipolesSSS
Outlook
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
12
Countdown LHC : Simple Magnets Count
Basis • We are at the rate of ~ 55
Magnets tested per month (sustainable)The testing would end in April 07
• We need to go up to ~ 62 magnets per month . In this case,The testing would end in January
07 • It all depends on many factors but
principally for the sake of this simple calculation, one needs to consider what % of magnets get repeated & so forth leading to raw testing figure of : ( 1706 + x %)
• The cut-off around 1893 as an example assumes x =11 % in this Figure
Projection To Finish (assuming no cryo shutdown in Dec 06)
0
100
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v-04
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ug
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v-05
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Ap
r-06
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v-06
Dec
-06
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-07
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-07
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r-07
May
-07
Date
Mag
net
s
Present-Rate 55 per Month
Rate 62 per Month
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
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Target 2007 : Simple Magnets Count
Basis • It would be judicious to
achieve a figure of ~ 69 magnets per month to finish by Nov 2006
• This rate of testing is desired to realise the objective of
“First LHC Collisions by Summer 2007”
&
Provide for contingencies
Projection To Finish (assuming no cryo shutdown in Dec 06)
0
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
1500
1600
1700
1800
1900
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-03
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-04
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-04
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-04
Ap
r-04
May
-04
Jun
-04
Jul-
04A
ug
-04
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-04
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-04
No
v-04
Dec
-04
Jan
-05
Feb
-05
Mar
-05
Ap
r-05
May
-05
Jun
-05
Jul-
05A
ug
-05
Sep
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No
v-05
Dec
-05
Jan
-06
Feb
-06
Mar
-06
Ap
r-06
May
-06
Jun
-06
Jul-
06A
ug
-06
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No
v-06
Dec
-06
Jan
-07
Feb
-07
Mar
-07
Ap
r-07
May
-07
Date
Mag
net
s
Present-Rate 55 per Month
Rate 62 per Month
Rate 69 per Month
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
14
How do we accelerate the testing of magnets ?
Our most precious resource is the bench occupancy time hence, one must
“Reduce the bench occupancy time”
• The bench occupancy time consists of
– Connect Time : Connection of Magnet to the CFB– Cooling Time : Cooling the Magnet to 1.9 K – Cold Test Time : Training the Magnet + Special Measurements– Warming Time : Warming the Magnet to 300 K– Disconnect Time : Disconnection of Magnet from the CFB (For a Dipole, this total should be theoretically 108 hrs.of which cold test time is 36
hrs. )
• To reduce the bench occupancy time, any OR all these times must be reduced
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
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Bench Occupancy Reduction Schemes
• Enhanced Cryo-Capacity in 2005 & resulting optimism
• Moderate Proposals (Presented at MTM Review Jan 05)– Fewer Single Stretch Wire Measurements for Arc-SSS magnets – Reduced Training Quenches beyond 7 TeV: 3 Quench Rule– Improved Production Control at warm : Diode Tests– Reduced duplication : WP04 Insulation Tests
• Additional [Radical] Proposals that could still be done – Schemes that curtail training to currents upto 11 kA (~ 6.5 TeV
operation) ; implies ‘training’ in the tunnel to go up in Energy– Reduce “ Connect Time” by not doing certain tests at warm on the
bench
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
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Cryo-Capacity 2004 & Estimates 2005
• The Average Wait+Cooling time was 45 hours & Wait+Warming time was 20 hours
• We are told to expect a gain of 50 % in CWS unit of cryogenics in 2005. so at least 1 more magnet in 300K-90K or 30K-300K phase
• We predict a Wait+Cooling time of ~ 30 hours & Wait+Warming time of ~15 hours
Average (Wait+Cooling) & (Wait+Warming) Dipole Magnets
0.00
10.00
20.00
30.00
40.00
50.00
60.00
Feb
ruar
y
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ch
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ril
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e
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gu
st
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ber
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ob
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vem
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Ho
urs
W+Cooling
W+Warming
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
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SUMMARY: Time Saving Schemes
Average Time to Test magnets (hrs)
Details Dipoles Arc-SSS
Present Future Present Future
Connect Time 30 29 82 52
Wait +Cooling Time
45 33 32 30
Cold Test Time 34 28 75 35
Warming Time 20 15 12 14
Disconnect Time 8 8 8 8
Total test Time 137 113 209 137
• Based on Moderate Proposals & Cryo improvements
Cold Test times include Magnetic Measurements (Special & Non special)
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
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• The gains only refer to Dipoles & Arc-SSS because we have No Experience with IR-SSS
• The calculation leads to 52 Dipoles & 16 Arc-SSS & i.e., 68 magnets could be tested per month, in a bench configuration of 8 Dipole +3 Arc SSS and leaving 1 Bench for IR-SSS
• However as it is obvious from above, the completion date cannot be based on a simple number count basis. The matter becomes much more complicated due to our boundary conditions…..throughput of Dipoles & Arc-SSS, matched bench allocation etc..
• An appropriate method to evaluate the projection date must take into account that the LHC ring is made up of different types of magnets which require appropriate bench mechanical & electrical configurations for testing
– 1232 Dipole Magnets– 360 ARC SSS Magnets– 82 IR SSS Magnets (DS + MS Type)– 32 IR SSS Magnets (DS_MQ Type)
1706 Total number of Magnets
Summary : Time Saved per magnet
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
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Projections: Accelerated Rate for Dipoles & ARC SSS & Optimistic Rate for IR SSS
Date Magnets per
Month DipolesMagnets per
Month ARC SSSMagnets per
Month IR SSSCumulative
DipolesCumulative ARC SSS
Cumulative IR SSS
Cumulative Total
Magnets per Month
Configuration
Nov-04 48 11 476 51 2 529 59 D-9 / AS-2 / IS-1
Dec-04 15 3 1 491 54 3 548 19Feb-05 45 10 1 536 64 4 604 56 D-8/AS-3/IS-1Mar-05 50 12 2 586 76 6 668 64Apr-05 50 15 2 636 91 8 735 67
May-05 50 15 3 686 106 11 803 68Jun-05 50 15 3 736 121 14 871 68Jul-05 50 15 4 786 136 18 940 69
Aug-05 50 15 4 836 151 22 1009 69Sep-05 50 15 4 886 166 26 1078 69Oct-05 50 15 4 936 181 30 1147 69Nov-05 50 15 4 986 196 34 1216 69Jan-06 15 3 1 1001 199 35 1235 19Feb-06 34 16 6 1035 215 41 1291 56 D-6/AS-4/IS-2Mar-06 38 18 8 1073 233 49 1355 64Apr-06 38 21 8 1111 254 57 1422 67
May-06 38 21 8 1149 275 65 1489 67Jun-06 38 21 8 1187 296 73 1556 67Jul-06 38 21 8 1225 317 81 1623 67
Aug-06 38 21 8 1263 338 89 1690 67Sep-06 38 21 8 1301 359 97 1757 67Oct-06 38 21 8 1339 380 105 1824 67
Nov-06 29 1 8 1368 381 113 1862 38
Dec-06 7 1368 381 120 1869 7Jan-07 1368 381 120 1869 0Feb-07 1368 381 120 1869 0Mar-07 1368 381 120 1869 0
Apr-07 1368 381 120 1869 0May-07 1368 381 120 1869 0
Basic Targets 1232 360 114Re-Tested 135.52 21.6 6.84Probable Target 1367.52 381.6 120.84Total Magnets 1869.96
Assumption : Testing Time : Dipole 113 hrs; Arc SSS 137 hrs
114 (IR SSS)=50 (MS) + 32 (DS) + 32 (DS-MQ Type)
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
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Assumptions
• All the moderate proposals mentioned would be implemented
• It is assumed that a figure of 1869 magnets will have to be tested including retests.
Retest rates: 11% dipoles,6% Arc SSS, 6% IR SSS
• It assumed that the magnets will be available for testing as and when desired
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
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Projections: Accelerated Rate for Dipoles & ARC SSS & Optimistic Rate for IR SSS
Highlights:
• Testing Time for Dipoles is ~113 hrs• Testing Time for ArcSSS is ~ 137 hrs•Testing Time for IR- SSS ~ 168 hrs?
Completion of testing of all MAGNETS
Dec 06
Assumption:
We can attain a figure of up to 69 magnets per month
Projection To Finish Dipoles(assumed no cryo shutdown in Dec 06)
-100
0
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
1500
Dec
-03
Jan-
04Fe
b-04
Mar
-04
Apr
-04
May
-04
Jun-
04Ju
l-04
Aug
-04
Sep
-04
Oct
-04
Nov
-04
Dec
-04
Jan-
05Fe
b-05
Mar
-05
Apr
-05
May
-05
Jun-
05Ju
l-05
Aug
-05
Sep
-05
Oct
-05
Nov
-05
Dec
-05
Jan-
06Fe
b-06
Mar
-06
Apr
-06
May
-06
Jun-
06Ju
l-06
Aug
-06
Sep
-06
Oct
-06
Nov
-06
Dec
-06
Jan-
07Fe
b-07
Mar
-07
Apr
-07
May
-07
Date
Mag
nets
Cumulative Yield Dipoles
Cummulative Yield SSS
Cumulative Yield IR-SSS
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
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Projections: With ~ 62 to 65 Magnets per month
Date Magnets per
Month Dipoles
Magnets per Month ARC
SSS
Magnets per Month IR SSS
Cumulative Dipoles
Cumulative ARC SSS
Cumulative IR SSS
Cumulative Total
Magnets per Month
Configuration
Nov-04 48 11 476 51 2 529 59 D-9 / AS-2 / IS-1Jan-05 15 3 1 491 54 3 548 19Feb-05 46 10 1 537 64 4 605 57 D-8 / AS-3 / IS-1Mar-05 49 12 1 586 76 5 667 62Apr-05 49 12 1 635 88 6 729 62
May-05 49 12 2 684 100 8 792 63Jun-05 49 12 2 733 112 10 855 63Jul-05 49 12 4 782 124 14 920 65
Aug-05 49 12 4 831 136 18 985 65Sep-05 49 12 4 880 148 22 1050 65Oct-05 49 12 4 929 160 26 1115 65Nov-05 49 12 4 978 172 30 1180 65Jan-06 15 3 1 993 175 31 1199 19Feb-06 37 16 4 1030 191 35 1256 57 D-6 / AS-4 / IS-2Mar-06 37 17 4 1067 208 39 1314 58Apr-06 37 17 6 1104 225 45 1374 60
May-06 37 17 6 1141 242 51 1434 60Jun-06 37 17 6 1178 259 57 1494 60Jul-06 37 17 6 1215 276 63 1554 60
Aug-06 37 17 6 1252 293 69 1614 60Sep-06 37 17 6 1289 310 75 1674 60Oct-06 37 17 6 1326 327 81 1734 60Nov-06 37 17 6 1363 344 87 1794 60Dec-06 5 17 8 1368 361 95 1824 30Jan-07 17 8 1368 378 103 1849 25Feb-07 3 12 1368 381 115 1864 15 AS-2 / IS-4Mar-07 5 1368 381 120 1869 5Apr-07 1368 381 120 1869 0May-07 1368 381 120 1869 0
Basic Targets 1232 360 114Re-Tested 135.52 21.6 6.84Probable Target 1367.52 381.6 120.84Total Magnets 1869.96
Assumption : Testing Time : Dipole 116 hrs; Arc SSS 170 hrs
114 (IR SSS)=50 (MS) + 32 (DS) + 32 (DS-MQ Type)
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
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Projections: With ~ 62 to 65 Magnets per month
Highlights:
• Testing Time for Dipoles is ~116 hrs• Testing Time for ArcSSS is ~ 170 hrs•Testing Time for IR- SSS ~ 240 hrs ?
Completion of testing of all MAGNETS
March 07
Assumption:
We can attain a figure of up to 65 magnets per month
Projection To Finish Dipoles(assumed no cryo shutdown in Dec 06)
-100
0
100
200
300
400
500
600
700
800
900
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1200
1300
1400
1500
Dec
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Ap
r-04
May
-04
Jun
-04
Jul-
04A
ug
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Sep
-04
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No
v-04
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Feb
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Mar
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Ap
r-05
May
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05A
ug
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v-05
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Feb
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Ap
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ug
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No
v-06
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-06
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-07
Feb
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Mar
-07
Ap
r-07
May
-07
Date
Mag
net
s
Cumulative Yield Dipoles
Cummulative Yield SSS
Cumulative Yield IR-SSS
Concerns & Worries
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
25
Possible Concerns & Worries for installation
1. IR-SSS – Testing :
• The testing of Insertion Region SSS is an uncharted territory to date and we need to ensure we have sufficient time for these within the existing boundary conditions.
• From our present limited experience, it takes a up to a 1 week to modify the bench to permit IR-SSS mechanical & electrical connections.
• 82 IR SSS are individually powered so one needs to provide at least the transfer function for powering & machine energy correlation even if detailed magnetic measurements are not done
• IR-SSS also need special Magnetic test cycles• Logistics, Transport (avoid all issues that plagued Arc
SSS in 2004)
– “OFF-THE-SHELF” Availability for installation ?
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
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Possible Concerns & Worries
2. Manpower & Continuity– Indian Associates
• With fixed one year contracts, there is continuous rotation of people, hence some are always on the learning curve. This could be a problem in an accelerated magnet testing scenario which requires continuity & stability.
– CERN AB-OP Staff• In case of 2006 early Accelerators start-up how
would the SM18 Operation cope with reduced Stable CERN support?
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
27
Possible Concerns & Worries
3. Is the production reliable that our test programme remains stable – Will additional tests like “Diode test” at cold be
introduced or means found otherwise (at warm) for production control?
4. Other (newer) demands on SM 18 operation– Dynamic effects at injection, sufficient time
resolution for decay/snapback, degaussing cycles etc, all need new additional studies. Even if conducted on fewer magnets, they take long time and upset the normal tests rhythm because the magnet remains on the bench a long time at cold. (and keeps a higher priority). Will similar (newer) requests be made ?
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
28
Possible Concerns & Worries
5. Can others cope with faster throughput?– ICS Consortium Contract Labour
• Do they have adequate manpower to absorb the increased work load
– Equipment Support• The fact that we have “Generalized Equipment
support as opposed to specialized support as found in 24 Hr. operation in CERN” causes delays in solving problems and hence reduces our ability to test magnets faster
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
29
Possible Concerns & Worries
6. ROCLA – ROCLA suffered from breakdowns in 2004, with dramatic effects;
similar issues would jeopardise our desired test rates – Presently the ROCLA operation staff do not work 24 hrs, but with the
projected magnets per month, it is imperative that a change in working hours will be required. Our experience with ICS says that these things do not happen overnight.
Connect, Total Bench Time per Dipole
0.00
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250.00
Fe
bru
ary
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rch
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y
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ne
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st
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pte
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er
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ve
mb
er
De
ce
mb
er
Month
Ho
urs
Connect
Total Bench TimeR
ocl
a P
rob
lem
s
12 B
ench
es O
per
atio
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( 3-
SS
S)
ICS
- 2
4 H
ou
rs
Pri
ori
ty S
etti
ng
s b
y O
P
4-B
ench
es f
or
SS
S
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SS
W@
War
m e
xcep
t D
2
3-B
ench
es f
or
SS
S
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
30
Conclusions
1. Different Projections with end-2006 goal in mind have been presented showing that testing of what we do know ( Dipoles & Arc-SSS) must go faster to permit more time for the unknown ( IR-SSS)
2. The IR SSS testing, particularly magnetic measurements will have to be based on sampled or Type testing and utilising all our known measurement systems and facilities both in SM18 and Block 4 on Prevessin site ( MAC Dec 04, Review Jan 05 )
3. Despite many unknowns we believe that there is a reasonable chance of terminating the test programme in time by end 2006 OR early months of 2007.
““Optimism is the faith that leads to achievement. Nothing Optimism is the faith that leads to achievement. Nothing can be done without hope and confidencecan be done without hope and confidence““
.....Helen Keller (American author and educator who was blind and deaf. 1880-
1968)
V. Chohan LHC Project Workshop-Chamonix XIV, 17-21 Jan. 2005
31
Thank You
Thanks to the OP Team for providing the Input for this talk.
Acknowledgements are also due to to all the past & present members of the SM18 Operation Team from DAE-India & AB Dept, CERN to bring the Tests Programme to the level where it is today, together with all the other Support Teams ( MTM-Equipment, Cryogenics, ICS, Power convertor)