Model Quadrupoles DOE Review of the LHC Accelerator Research Program July 13-14, 2009

Physics Division Future PlansGianLuca Sabbi, LBNL
July 13-14, 2009
Gian Luca Sabbi
GianLuca Sabbi, LBNL
Design Features
Next steps
R&D Goals
Work plan through FY10
Two support structures:
- TQS (shell based)
- TQC (collar based)
TQC
TQS
Issues:
Localized degradation, not systematic
Best results are still ~8% below SSL
For TQS02 models:
TQ01
30 coils fabricated, distributed production line
11 tests performed (FNAL, LBNL and CERN)
Surpassed 200 T/m with 10% margin (TQS02a/c)
All training quenches >200 T/m in TQS02c/d
SSL 4.4K
SSL 1.9K
LARP DOE Review, July 13-14, 2009
Interpretation: conductor instability at 1.9K, enhanced by local degradation:
Limiting quenches in the same coil & location (c23 ramp) at 4.5K and 1.9K
1.9K stability limit in magnet is lower (half) than expected from strand data
200 T/m
TQM03 Model (FNAL core program)
Magnetic mirror for testing of single coils
Mechanical support through bolted shell
One virgin coil was recently tested:
1.9 K quench levels are well above 4.5 K
Corresponds to expected margin increase
TQS03 Model (LARP + FNAL / LBNL core programs and CERN)
Full quadrupole coil in shell-based structure
Same preload as in previous TQS models
Four virgin coils, under testing at CERN:
Confirm expected improvement 4.5K to 1.9K
Verify reproducibility over a set of four coils
Goal: verify conductor performance in a well defined magnet environment
Next Phase: 120 mm Quadrupoles
IR Studies show large aperture quads are required for L=1035 cm-2 sec-1
Phase 1 (L=2 1034 cm-2sec-1) will use NbTi Quads with 120 mm aperture
The same aperture was chosen for the next series of Nb3Sn models (HQ)
Full qualification based on Phase 1 luminosity requirements
Providing performance reference for Phase 2 upgrade design
Aiming at:
HQ Progress since the 2008 DOE Review
2008 June Presented conceptual designs for 114 and 134 mm bore
July Selection of 120 mm quadrupole aperture for Phase 1
Aug. Practice cables fabricated, test windings completed
Aug. Cable and coil cross-section geometry finalized
Sep. Winding and curing tooling in procurement
Nov. 3D magnetic and coil design completed
2009 Jan. Mechanical analysis completed, shell in procurement
Feb. Coil parts, reaction/potting tooling in procurement
Mar. All structure components in procurement
Apr. Two cable UL fabricated (modified 54/61)
June (Practice) coil 1 winding/curing completed
June Reaction and potting tooling received
June Three cable ULs fabricated (modified 54/61)
July Coil 1 reaction and coil 2 winding completed
Design and fabrication timeline is comparable to NbTi technology
Magnetic design FNAL & LBNL
Quench protection and heaters LBNL
Winding and curing tooling design LBNL & FNAL
Reaction and potting tooling design BNL
Instrumentation traces LBNL
Coil reaction and potting BNL & LBNL
Coil handling and shipping tooling BNL
Structure fabrication and test LBNL
Magnet assembly LBNL
Magnet test FNAL
HQ Design Features and Parameters
Coil peak field of 15.1 T at 219 T/m (1.9K un-degraded SSL: 19.5 kA)
190 MPa coil stress at SSL (150 MPa if preloaded for 180 T/m)
Stress minimization is primary goal at all design steps (from x-section)
Coil and yoke designed for small geometric and saturation harmonics
Full alignment during coil fabrication, magnet assembly and powering
Width: 15.15 mm
Mid-thickness: 1.44 mm
Keystone angle: 0.750
46 turns/quadrant
Test windings
Sub-element deformation
Edge facets
Cable insulation:
Reference radius 40 mm (2/3 aperture)
Small geometric harmonics (2 wedges)
Saturation b6 ± 1 unit from 0 to 20 kA
Optimized for 120 T/m gradient
End design optimized for minimum field
No additional spacers in the ends
120 T/m
Main structural components:
Aluminum shell: 25 mm thick, OD = 570 mm (same as LHC dipole)
4-split iron yoke
Iron pads provide space for axial rods and cooling channels
Iron masters house 50 mm wide bladders, loading and alignment keys
Aluminum collars align poles while transferring pre-load to the coils
20 MPa max. tension at 219 T/m
Axial forces:
Mid-plane stress:
193 MPa @ 219 T/m
- Rstrip 300 K = 5.7 ohms
- Rstrip 4.2 K = 3.9 ohms
- Istrip = 67 A => 75 W/cm2 at 4.2 K
- 15.5 mm wide
- Rstrip 300 K = 3.95 ohms
- Rstrip 4.2 K = 2.7 ohms
- Istrip = 93 A => 75 W/cm2 at 4.2 K
Each layer has two independent heaters , voltage taps, z/q strain gauges
Layer 1 heater parameters:
Layer 2 heater parameters:
Coil Fabrication:
Alignment keys in curing cavity
Alignment pins for reaction / potting
Structure pre-assembly:
Assembly and pre-loading:
Design Features
Reaction tooling
Practice Coil 1 Reaction
Step 3 temperature is increased from 640C in TQ to 665C in HQ
15 T critical current is about half of 12 T different trade-offs
Revised length/angle of flexing cuts
Modifications for heaters, splices
Axial gaps during winding
Instrument.
Coil-spacer fit
Flexing cuts
HQ Budget in FY09 and FY10
HQ cabling (Materials R&D): +25k$ for one additional run (108/127)
Some adjustments under discussion for FY09-Q4 to optimize schedule
Complete HQ01; HQ01b retest (replacing 1-2 coils); start HQ02 coils
Testing of single coils in the mirror structure is also being considered
FY09
FNAL
LBNL
BNL
Total
D (%)
K$
Labor
HQ01 models will establish baseline performance:
Mechanical support, quench training
Conductor performance, stress degradation
Quench protection and instrumentation
In the meantime, Phase 1 requirements will be better defined
Parallel studies to understand implications for Nb3Sn magnets
HQ02 models will address key areas needing improvement
Field quality (geometric, saturation, magnetization)
Mechanical structure, alignment
Cooling, radiation hardness
HQ optimization results will provide a basis for the 2-m models (QA)
Provided technology basis for Long Quadrupoles (LQ)
Further optimization and conductor studies are in progress
HQ Model Quadrupoles:
Harness the full potential of Nb3Sn for the LHC upgrade
Key step forward toward an accelerator quality design
Phase 1 specifications will guide further optimization
Optimized HQ will provide technology basis for 2-m QA
1000010500110001150012000125001300013500140001.92.12.32.52.72.93.13.33.53.7Current (A)Temperature (K)
1100011200114001160011800120001220012400126001.82.22.63.03.43.84.2Current (A)Temperature (K)
0510152025309101112131415
TQS03a Coils 30-31-32-33 Short Sample estimateExtracted strand data, self-field correction: 0.536 T/kALBNL XSLBNL RWBNL XSParameterization 4.23 KB peak innerParameterization 4.4 KParameterization 1.9 K
100150200250300350507090110130150Coil Aperture [ mm ]Short Sample Gradient [ T/m ]
TQ [8]-[9]& LQ [10]HQ
100150200250300350507090110130150Coil Aperture [ mm ]Short Sample Gradient [ T/m ]
TQ & LQNb
35
cm
-2
s
-1
-20020406080100120140-0.200.20.40.60.811.2Contact pressure (MPa)l1p tipl1s tipl2p tipl2s tip293 K 4.2 K 180 T/m 219 T/m
6Structure Design and Fabrication Mon 2/2/09Wed 11/18/09
7Structure ProcurementMon 2/2/09Tue 7/21/09
8Structure pre-assemblyWed 7/22/09Wed 9/30/09
9Mechanical modelThu 10/1/09Wed 11/18/09
10HQ01 ModelFri 7/17/09Wed 3/10/10
15Coil 3 React/ImpregFri 8/21/09Fri 9/25/09
16Coil 4 React/ImpregFri 8/28/09Fri 10/2/09
17Coil 5 React/ImpregMon 9/28/09Fri 10/30/09
18Coil 6 React/ImpregMon 10/12/09Fri 11/13/09
19Magnet AssemblyThu 11/19/09Tue 1/5/10
26Coil 7 React/ImpregWed 12/23/09Thu 2/4/10
27Coil 8 React/ImpregFri 1/22/10Thu 2/25/10
28Magnet AssemblyWed 3/24/10Tue 4/27/10
34Coil 9-12 React/ImpregThu 6/24/10Fri 10/1/10
3/10
7/1
AprMayJunJulAugSepOctNovDecJanFebMarAprMayJunJulAugSepOct

Model Quadrupoles DOE Review of the LHC Accelerator Research Program July 13-14, 2009

Documents

Transcript of Model Quadrupoles DOE Review of the LHC Accelerator Research Program July 13-14, 2009