Magnet Systems Introduction

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Magnet Systems Introduction
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Coil/Cryostat Common Features

• All cryostats will be located inside the shielded
  space of the experimental area
• Cold masses are supported (vertically, axially,
  horizontally) with cold-warm rods with rotational
  capability
• All coils will be electrically insulated with a
  combination of Kapton and fiber-glass tape and
  epoxy impregnated
• All conductor joints (soldered, lap joints) are
  external to the winding packs
• Superconducting buses connect the coils to the
  vapor cooled leads in control dewars outside
  shield wall
• All coils have voltage taps feeding quench
  detection
• 2 kV maximum quench voltage
• LN2 traced thermal radiation shields
• Stainless steel vacuum shells with gravity
  supports to floor embedments
• Temperature margin ³ 1.5 K Fraction of critical
  current 0.4

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Cryostats in BNL AGS Facility
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Field Requirements
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PS Cryostat Features

• Cryostat mass is 52,600 kg
• Peak field is 5.7 T on winding
• Coils are externally supported by 6061-T6 Al
  shells
• Subjected to 98.7 W of nuclear heat load into
  cold mass
• Helium bath cooled with 4.5 K, 2-phase He
• Helium vessel is an ASME pressure vessel designed
  for a working load of 5 atm (quench)
• Coil has room temperature iron ground water
  shield (post-CDR)
• Coil conductor

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PS Drawing
Coil
Al shell
He vessel
Thermal shield
Vacuum vessel
Axial supports
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TS Cryostat Features

• Mass
• TSu is 28,800 kg
• TSd is 27,800 kg
• Peak field is 3.5 T on winding
• Coils are self-supporting in hoop, wound on
  H-shaped stainless steel mandrels
• No nuclear heating
• Cu shells surround winding and are conduction
  cooled with 2-phase He at 4.5 K
• Stainless steel vacuum vessel
• Conductor

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TS Drawing
Stainless steel mandrel with tapered flanges
Coil
LN2 cooled thermal shield
Vacuum can
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DS Cryostat Features

• Mass is 52,900 kg
• Peak field is 2.0 T on winding
• Coils are self-supporting in hoop, wound on
  H-shaped stainless steel mandrels (like TS)
• No nuclear heating
• Cu shells surround winding and are conduction
  cooled with 2-phase He at 4.5 K
• Stainless steel vacuum vessel
• Coil has room temperature iron cosmic ray shield
• Conductor

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DS Drawing
Vacuum can
Stainless steel mandrel
Coil with Cu shells
LN2 shield
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Safety Items Check List

• Magnetic fields
• Structural loads
• Electromagnetic
• Thermal
• Gravity
• Quench detection and protection
• High voltage (2 kV quench voltages)
• Cryogenic fluids/volumes
• He (5 atm quench pressure in PS)
• LN2
• Vacuum
• Installation lifts