Status Report on the Design, Fabrication and Measurement of 29 quads for ATF2

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Status Report on the Design, Fabrication and
Measurement of 29 quads for ATF2

• By Cherrill Spencer, SLAC, for ATF2 project
  meeting on SATURDAY 4th February 2006

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4. General Assembly

• 1). Overview of general assembly QEA-D32T180.

NOT FINAL DRAWING. DO NOT USE
32mm bore 180mm core length 48 turns per water
cooled coil Max gradient 55 T/m
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ATF2 quadrupoles QEA-D32T180

• Are 8 quadrupoles in the extension of the ATF
  extraction line
• Are 6 quads in matching section of ATF2 beamline
• Are 14 quads in final focus section of ATF2 (
  aside from QF1QD0)
• Decided an existing KEK quad called the TOKIN
  3390 (QB4 style) would be basis of the design
  for the 28 ATF2 quads listed above.
• See R. Sugaharas talk to this meeting for
  summary of history to-date of the design,
  fabrication and measurement of these quadrupoles
• Spencers activities during trip to IHEP, 6th
  -14th Dec 05
• Observe main trim coil winding forms coil
  winding potting shops
• Inspect first 4 wound trim coils size,
  resistance and inductance OK
• Observe the brand new Electric Discharge Machine
  (EDM)
• Inspect 4 quadrants of the first quads steel
  core before and after EDMing of the
  hyperbolic-shaped poletips
• Core quadrants assembled and toleranced
  dimensions near poletips measured with micrometer
• All toleranced dimensions are within tolerance
• First core sent to CMM for measurement of
  hyperbolic poletips

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QEA-D32T180 COIL DRAWING- drawn by IHEP
NOT FINAL COIL DRAWING DO NOT USE Coils have 48
turns of 6mm square Copper conductor
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Trim coil winding form (left) and main coil
winding form set-up on winding machines
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IHEP film potting apparatus (left) Dr Xuwen Dai
measuring dimensions of first trim coils
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First core after all machining finished , in the
IHEP Machine Shop. 9th Dec 2005
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First main coil, before trim added, before
pottingEarly January 2006
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First main coil after trim added and both potted
together. 9th January 2006
G10 fillers where turns decrease
Epoxy has no Al2O3 filler and so is transparent.
Trim coil
Ground wrap has become transparent through the
potting process
Dimensions of first coil meet tolerances.
Resistance as expected. A 2.5mm ball was pushed
through the conductor, indicating the water
passage is clear.
Two 1st coils been placed over 2 core quadrants-
everything fits OK.
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First coil package sliced so we could inspect
quality of winding and potting
Conclusions Main and trim coil winding is
satisfactory. Potting process (with wrapped film
to contain the potting epoxy, no mould) works
very well. All dimensions to spec.
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First fully assembled ATF2 quadrupole, 17th
January 2006
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First ATF2 quad on measuring stand at IHEP.
Rotating coil being set-up. 19th January 06
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ATF2 quad gradient versus current measured with
Hall Probe saturated as expected
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Summary of prelim measurement results on first
ATF2 quad at IHEP

• Magnet measured up to 150 amps. Cooling is fine.
• Effective length longer than predicted by usual
  rule of thumb and it decreases by 0.47 from 50
  to 135 amps.
• Average effective length over all currents
  19.849 cm
• Quad is 99.27 efficient at 50 amps
• Quad is 97.32 efficient at 100 amps
• Quad is 85.43 efficient at 135 amps
• With actual effective length and max K1 2.5 need
  gradient of 54.76T/m, which is achieved with
  136.2 amps
• Half the quads will need PS that go to 150 amps

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First quad measured with Hall probe By values
along X at Z center
Shape of field looks good. Multipoles will be
measured with new rotating coil next week (6-10
Feb) and compared against tolerances. Standardizat
ion procedures will be finalized next week.
Integrated strength versus current data what
can ATF2 PS control system deal with? Each magnet
has own polynomial or not?