1 / 26

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

BNL - FNAL - LBNL - SLAC. Model Quadrupoles DOE Review of the LHC Accelerator Research Program July 13-14, 2009 Gian Luca Sabbi. Presentation Outline. 90 mm aperture Model Quadrupoles (TQ): Design Features Progress since the last DOE review Next steps

rajah-stone
Download Presentation

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

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. BNL - FNAL - LBNL - SLAC Model Quadrupoles DOE Review of the LHC Accelerator Research Program July 13-14, 2009 Gian Luca Sabbi

  2. Presentation Outline • 90 mm aperture Model Quadrupoles (TQ): • Design Features • Progress since the last DOE review • Next steps • 120 mm aperture Model Quadrupoles (HQ): • R&D Goals • Coil and Structure Design • Status of the HQ01 model fabrication • Work plan through FY10

  3. LARP Technology Quadrupole (TQ) • Double-layer, shell-type coil • 90 mm aperture, 1 m length • Two support structures: • - TQS (shell based) • - TQC (collar based) • Target gradient200 T/m TQC TQS Winding & curing (FNAL - all coils) Reaction & potting (LBNL - all coils)

  4. TQ Status at the 2008 DOE Review • Two coil/model series using different wire design • 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 TQ01 OST-MJR 54/61 TQ02 OST-RRP 54/61 61 Results of TQS02c test (CERN) • Issues: • Variability in the coil production process • Localized degradation, not systematic • Best results achieved by coil selection • Best results are still ~8% below SSL • For TQS02 models: • Best results were obtained at 4.4 K • Quenchlevels at 1.9K were 5-10% lower SSL 1.9K SSL 4.4K

  5. TQS02c Characterization at 1.9K Additional tests performed at CERN in September 2008: 200 T/m • 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

  6. TQ Tests with OST-RRP 108/127 Strand Goal: verify conductor performance in a well defined magnet environment • 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

  7. TQS03 Performance Expectations

  8. 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:

  9. 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

  10. HQ Task Distribution by Laboratory • Cable design and fabrication LBNL • Magnetic design FNAL & LBNL • Mechanical design LBNL • Coil parts design and procurement FNAL • Quench protection and heaters LBNL • Winding and curing tooling design LBNL & FNAL • Reaction and potting tooling design BNL • Instrumentation traces LBNL • Coil winding and curing LBNL • Coil reaction and potting BNL & LBNL • Coil handling and shipping tooling BNL • Structure fabrication and test LBNL • Magnet assembly LBNL • Magnet test FNAL

  11. 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

  12. Coil and Cable Design Coil parameters: • 120 mm aperture, 2 layer • One wedge in each layer • 46 turns/quadrant Cable parameters: • 35 strands, 0.8 mm diam. • Width: 15.15 mm • Mid-thickness: 1.44 mm • Keystone angle: 0.750 Cable insulation: • Glass sleeve, 0.1 mm thick Sub-element deformation Edge facets Test windings

  13. 120 T/m Magnetic Design and Field Quality • 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

  14. Mechanical Design • 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

  15. Mechanical Analysis • Pre-loading for 219 T/m • Pole contact pressure: • 140 MPa compression at 0 T/m • 20 MPa max. tension at 219 T/m • Axial forces: • E.m. force: 1372 kN • 620 kN applied at 4.2 K • Mid-plane stress: • 193 MPa at 219 T/m 193 MPa @ 219 T/m

  16. Heaters and Instrumentation Traces Each layer has two independent heaters , voltage taps, z/q strain gauges Layer 2 heater parameters: Layer 1 heater parameters: - 10.79 mm wide - 2.166 m long strip per side - 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 - 2.158 m long strip per side - Rstrip 300 K = 3.95 ohms - Rstrip 4.2 K = 2.7 ohms - Istrip = 93 A => 75 W/cm2 at 4.2 K Layer 2 VT05 VT10 VT03 VT09 VT06 VT08 VT07 VT04

  17. Coil and Structure Alignment • Alignment is controlled at all steps • Coil Fabrication: • Winding: mandrel to layer 1 to layer 2 • Alignment keys in curing cavity • Alignment pins for reaction / potting • Structure pre-assembly: • Pins between shell and yoke • Aluminum collars and pole keys • Assembly and pre-loading: • Master keys maintain alignment • Cool-down and excitation: • Pole keys remain in compression

  18. Accelerator Quality in LARP Models

  19. Progress on Coil Fabrication Layer 1 Winding Layer 1 Curing Layer 2 Winding

  20. Progress on Coil Fabrication (2/2) Reaction tooling Preparations for coil transfer Practice coil 1 in reaction tooling

  21. 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

  22. Practice Coil Experience • In progress: • Improve fitting of outer layer parts • Revised length/angle of flexing cuts • Modifications for heaters, splices • To be addressed: • Step between layers after curing • Axial gaps during winding • End shoe holders during reaction Coil-spacer fit Flexing cuts Instrument. wire reliefs Nb3Sn-NbTi splice shims Layer 1-2 step after curing

  23. HQ Schedule FY09-FY10

  24. 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

  25. HQ Optimization toward 2-meter scale-up • HQ01 models will establish baseline performance: • Mechanical support, quench training • Conductor performance, stress degradation • Quench protection and instrumentation • Field quality • 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)

  26. Summary • TQ Model Quadrupoles: • Surpassed 200 T/m performance target with 10-15% margin • Provided technology basis for Long Quadrupoles (LQ) • Further optimization and conductor studies are in progress • HQ Model Quadrupoles: • Significant increases in field, force and stress levels • 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

More Related