Long%20Racetrack%20(LR)%20Strategy%20Giorgio%20Ambrosio

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Long Racetrack (LR) StrategyGiorgio Ambrosio
DOE review - FNAL June 12-14 2006

• OUTLINE
• LR RD goals plans
• Long Racetrack design (overview)
• LRS01 Readiness Review
• Schedule and budget
• Conclusions

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Length Scale-Up Plan
LENGTH SCALE-UP CHALLENGE No Nb3Sn accelerator
magnet longer than 1m has ever been built LARP
should make a successful 4m long quadrupole by
end of 09
2006 2007 2008 2009
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Long Racetrack - GOALS

• The main goal is to develop long Nb3Sn coils
  fabrication technology (winding, curing,
  heat-treatment, impregnation, handling)
• ? target is to reproduce performance of short
  coils
• ? focus is on coil (Iss) more than magnet
  performance (training)
• Coils will be tested in an Al-shell-based
  supporting structure (preloaded using bladders
  and keys) in order to verify the use of this
  concept for long magnets

Performed at BNL
Developed at LBNL
Coil layout two flat double-layer racetrack
coils Technology successfully developed at LBNL
and successfully modified at FNAL
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Long Quadrupole issues I

• Cable and insulation
• Fabricate long (300 m) Nb3Sn cables
• Insulate long Nb3Sn cables sleeve/tape/braided-on
  -cable
• Coil winding and handling (in all phases)
• Tooling and procedures
• Heat Treatment (Nb3Sn expansion different CTE)
• X-section azimuthal gap as LARP TQ models
• Ends (free vs. confined)
• Pole gaps (how many? how much?)
• Wedges segmented vs. single-piece

LM/DS
LM
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Long Quadrupole issues II

• Impregnation
• Coil orientation vertical vs. angle
• Epoxy flow slow impregnation vs. pot-life
• Epoxy input single vs. several ports
• Coil-pole interface bonding vs. sliding surface
• Instrumentation and Quench Protection
• Quench protection of long Nb3Sn magnets
• Long quench heaters
• Magnet assembly
• Uniform pre-stress application by
• (i) Bladderkey tech.,
• (ii) Collarsskin
• End support and pre-load

LM
TQ
LM
TQ
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Long Racetrack RD - Plan

• Short Racetrack (SRS01), to validate technology
  transfer to BNL
• Same as LBNL Small Racetrack series
• Long Racetrack (LRS01), 1st test of long coils,
  as simple as possible
• Very similar to SRS01, except a few design
  modifications for long coils
• Side rails instead of horse-shoe,
• Larger yoke OD, thicker shims and coil skins

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Supporting structure - plan

• Al-shell-based supporting structure (preloaded by
  bladders--keys) have successfully been used in
  1m-long magnets.
• ? Long magnets require long shells.
• PLAN
• design, procure and assemble a supporting
  structure with long shell
• Test with a dummy coil package (at LBNL)
• Pressure sensitive paper and strain gauges
• Optimize structure
• Test with a dummy coil package (at BNL)
• Possibly using real coil parts and practice coil
• Use for LRS01 and LRS02

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Technology transfer LR ? LQ

• GOAL to maximize the transfer of technology,
  information and expertise from the Long Racetrack
  RD to the Long Quadrupole RD
• The lead engineer of the Long Quadrupole RD
  (Fred Nobrega, FNAL) is involved in all steps of
  the Long Racetrack RD (design, assembly, test
  and analysis), and will visit BNL during key
  operations (winding, impregnation, coil
  inspection )
• The lead technician of the Long Quadrupole RD
  (Marty Whitson, FNAL) will be at BNL during the
  major steps of the coil fabrication for LRS01 and
  LRS02
• The L2 coordinator of Supporting RD (G.
  Ambrosio) is coordinating and over-viewing all LR
  activities
• Trips planned in July-Sept. PC winding,
  impregnation and inspection

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LRS01 Design Report
TABLE OF CONTENTS 1. INTRODUCTION 2.
CONDUCTOR CHARACTERISTICS By A. Ghosh 3.
MAGNETIC DESIGN By P. Ferracin 4. COIL
FEATURES AND FABRICATION By J. Schmalzle,
and D. Dietderich 5. MECHANICAL DESIGN By
P. Ferracin, D. Cheng, and R. Hafalia 6. MAGNET
ASSEMBLY By D. Cheng, R. Hafalia, P.
Ferracin, and J. Schmalzle 7. QUENCH PROTECTION
By J. Muratore 8. COIL INSTRUMENTATION
By G. Ambrosio, and P. Wanderer References
https//dms.uslarp.org/MagnetRD/SupportingRD/LongM
agnetDevelopment/LRS01_design_V18.doc
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Long Racetrack - Design
Parameter Unit
Cable type SM
N? of double-layer coils 2
Number of turns per layer 21
Strand diameter mm 0.700
Number of strands 20
Cable width (bare) mm 7.793
Cable thickness (bare) mm 1.275
Insulation thickness mm 0.092
Cu/Sc ratio 0.90
Jc(12 T,4.2 K) A/mm2 2800
Bpeak(4.2 K) T 12.23
Iss (4.2 K) kA 10.80
Iss (4.2 K) per strand A 540
Inductance _at_ Iss (4.2 K) mH/m 1.5
Energy _at_ Iss (4.2 K) kJ/m 86
Fx per quadrant _at_ Iss kN/m 1903
Fy per quadrant _at_ Iss kN/m -9
Fz per quadrant _at_ Iss kN 20
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2D mechanical design

• Low pre-stress rigid boundary
• Pre-stress provided by
• Bladder and keys (293 K)
• Aluminum shell thermal contraction (4.2 K)
• After cooldown
• Peak coil stress 35 MPa
• Most of the force to the rails and pole
• At peak field
• Current has opposite direction in coil A and B
• Peak coil stress 75 MPa

Aluminum
Iron
A
B
Coil
S. steel
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LR longitudinal design

• Aluminum shell
• Single piece
• Length 3.6 m
• Iron yokes
• 50 mm thick laminations
• Iron pads
• Half length (1.8 m)
• Stainless steel skins
• Full length (3.6 m)
• Bladders
• Half length (1.8 m)
• Keys and shims
• Half length (1.8 m)

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LRS01 Readiness Review
April 24-25

• Given the upcoming results from SRS01, the
  fabrication and delivery of various parts and
  tooling, and the inspection and commissioning of
  those parts and tooling, the committee feels the
  program should keep proceeding.

• We do feel that several commissioning plans and
  detail designs should be more carefully
  documented.
• Extend the what if analysis to include
  success in the LRS01 test and how the program
  might be extended in this scenario.
• For instance, a mirror race track configuration
  could test other regions of the coils for
  degradation and coil prestress / end load effects

Partially done, partially in progress
Possible back-up plan in FY08
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Long Racetrack Schedule
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Long Racetrack ? Long Quad

• Expertise and test results of the Long Racetrack
  RD will be very valuable for the Long Quadrupole
  RD
• LQ coil design review Feb 9, 07 ? Feedback by
• LR practice coil fabrication and inspection
• LRS01 coils fabrication
• LRS01 magnet test
• LQx01 coil fabrication start Nov 6, 07 ?
  Feedback to coil fabrication procedures by
• All of the above LRS02 coils fabrication and
  magnet test
• LQ mechanical design selection May 15, 07 ?
  Feedback by
• LR supporting structure tests at room temperature
• LRS01 magnet test

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FY07 budget (in progress)

• Complete coil fabrication and assembly of LRS01
• Coil fabrication and assembly of SRS02 and LRS02
• Test of Supporting Structure
• Test LRS01, SRS02 and LRS02

       k BNL FNAL LBNL
  Long Magnet Development          
FY06 Racetrack coil fab test Schmalzle 1515 1399 24 92
  Racetrack supporting structure Ferracin 222   222
       
FY07 Racetrack coil fab test Wanderer 850 594 36 220
  Extra coil    132 132    

• Coordination through
• Weekly conference calls or video-meetings of LR
  working group (BNL, LBNL, FNAL)
• Weekly reports by task leaders
• Minutes, reports, drawings, pictures, on the
  LARP web site

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Conclusions

• The Long Racetrack RD has almost completed the
  1st phase (Technology Transfer LR design)
• SRS01 will be tested next week
• The design of LRS01 is almost complete
• Successfully passed LRS01 Readiness Review
• Despite some delays the Long Racetrack RD is on
  track to give very valuable feedback to the LQ
  RD
• ? Feedback to LQ coil tooling design
• Feedback to LQ coil fabrication procedures
• Feedback to LQ mechanical design selection