HiLumi-LHC / LARP Conductor and Cable Internal Review October 16 th and 17 th 2013 H. Felice LARP Short Magnets Fabrication and Test experience relevant to QXF conductor and cable specifications
Jan 02, 2016
HiLumi-LHC / LARP Conductor and Cable Internal ReviewOctober 16th and 17th 2013
H. Felice
LARP Short MagnetsFabrication and Test experience
relevant to QXF conductor and cable specifications
H. Felice 2
What is a successful magnet?
A magnet in which every single stage of fabrication has been successful
A magnet will be considered successful when I quench > 90 % Iss
10/17/2013
LARP history illustrates the involvement of each of these steps in magnet success and failures…
Cable Coil Fabrication Assembly - PreloadStrandDesign
H. Felice 4
From TQS02 series to TQS03 series
TQS02c •High RRR (>200)• 70 microns filament• 47 % Cu fraction• Jc (12T, 4.3 K) 2925 A/mm2
Tested at CERN
TQS03• High RRR (>200)• 50 microns filament• 54 % Cu fraction• Jc (12T, 4.3 K) 2770 A/mm2
Tested at CERN
205 – 210 T/m
220T/m
Moving from 54/61 to 108/127 improved performances at 1.9 KIn TQ
10/17/2013
220 T/m 238 T/m
H. Felice 5
TQS03 series and stress limit
-280-260-240-220-200-180-160-140-120-100
-80-60-40-20
0
Ti pole L1 pole L1 mp L2 pole L2 mp
Azi
mut
hal s
tres
s (M
Pa)
TQS03a
TQS03b
TQS03c
TQS03d
With Lorentz forces at 12 kA
10/17/2013
4 tests: TQS03 a, b, c and d
• performed with variable pre-stress• TQS03a: 120 MPa• TQS03b: 160 MPa• TQS03c : 200 Mpa• TQS03d: 120 MPa
After cool-down
-260-240-220-200-180-160-140-120-100
-80-60-40-20
0
Ti pole L1 pole L1 mp L2 pole L2 mp
Azim
utha
l str
ess (
MPa
)
TQS03a
TQS03b
TQS03c
TQS03d
H. Felice 6
TQS03 training
10/17/2013
TQS03 series demonstrated- Progressive degradation: but only 5 % from a to c- Permanent degradation beyond 200 MPa preload- QXF should have margin
• Magnet: pole turn (preload) / max midplane stress (excitation)• TQS03a: - 120 / -190 MPa• TQS03b: - 160 / -240 MPa• TQS03c : - 200 / -260 Mpa• TQS03d: - 120 / -190 Mpa
• Quench location:Midplane area
H. Felice 7
HQ series overview
HQ01 a-b-c-d-eMagnets with mixed coilsCoils 1-2-8-9 => 54/61Coils 3-4-5-6-7 => 108/127
Performance (LBNL and CERN)• 4 magnets => 70 to 85 % Iss at 4.4 K• HQ01e test at CERN => 85 % at 1.9
K
HQ02a and a2Same conductor in all coilsCoils 15-16-17-20 => 108/127
Performance (FNAL)• 98 % at 4.5 K• 89 % at 2.2 K
A. GodekeA. Godeke
10/17/2013
2 of each / magnet
H. Felice 8
HQ series performance overview
HQ01 series
HQ02
Reached 80% in 2 quenches
Good memory
What changed? • The coil fabrication
• Cable with Stainless steel core
HQM04
97% at 4.5 K
94% at 2.2 K
Maxim Marchevsky Guram Chladidze
10/17/2013
H. Felice 9
Impact of coil fabrication
Review of the coil fabrication process and designÞ High compaction of the winding during fabricationÞ Tooling and coil design oversight: no margin to allow for cable expansionÞ Risky end design
Suspected to be the cause of conductor degradation in potted coils
Main requirement for HQ02 coils: using the same tooling as HQ01•Accounting for dimensional changes and interlayer insulation
Smaller cable with smaller strand => 0.778 mm diameter strand => 14.8 mm x 1.375 mm
Axial gap size 4 mm/m•Revision of the end parts design
10/17/2013
Lead end
R, Hafalia, S, Caspi
H. Felice 10
HQ experience applied to QXFconductor
• Cable dimensional change accounted for in the magnetic design and tooling design
• 4.5 % in thickness and 2 % in width in ROXIE cross-section• Design made with reacted cable dimensions• Based on HQ and LQ experimental data
Importance to provide actual cable dimensional changes data for QXF cable to magnet designers
10/17/2013
H. Felice 11
Impact on coil fabrication schedule
Last HQ01 coil #9 completed end of 2010HQ01d and e tested starting April 2011
1st Mirror test at FNAL HQM01
2nd Mirror test at FNAL HQM02• 1 less turn• 91 % Iss at 4.6 K• 89 % Iss at 2.2 K
3rd Mirror test at FNAL HQM04• New end parts• New cable
HQ02 tested at FNAL
To validate compaction theory09/2011
05/2013
05/2012
04/2011
• Unforeseen change of cable in the case of HQ02 delayed strongly the magnet production
• QXF 2nd generation cable should be defined very early to facilitate implementation
10/17/2013
H. Felice 12
HQ Winding Experience
HQ01: 1st generation of coils• 2 pass cable• Mechanically stable
HQ02: 2nd generation of coils
• 1 pass cable to implement the stainless steel core• “Easy” popped strands noticed by technicians in some coils
• Easily fixable
HQ02 experience => Learning experience on how to handle less mechanically stable cables
10/17/2013
D. Dietderich - F. Borgnolutti
H. Felice 13
Impact of SS core in HQ performance
10/17/2013
X. Wang, J. DiMarco, M. Marchevsky – Guram Chladidze
HQ01 / HQ02 performance
• Beneficial effect on ramp rate dependence
• Beneficial effect on field quality
H. Felice 14
Summary
10/17/2013
• LARP short models performance widely influenced by all the production chain
• Best examples: HQ01 to HQM04 / HQ02• With coil fabrication improvement => performance improvement
• despite low RRR in coil 15
• What to remember from short model program for QXF
• Cable• Beneficial effect of the core cable on field quality and ramp rate dependence• let’s keep in mind the potential delay to implement a new cable design
• Coil fabrication / tooling design: • Data for Effective dimensional changes in the design
• Assembly: Stress level in conductor => TQS03 is a good guideline