J.H. Chrzanowski

1
Modular Coil Cooling Issues With Baseline
Status of Cooling RD
James H. Chrzanowski
Modular Coil Winding Cooling Workshop June 10,
2004 PPPL
2
Cost or schedule Risk

• 1- Cooling Scheme
• The complex geometry of the proposed chill plate
  cooling scheme could possibly add additional time
  to the installation process
• Fitup of the plates and attachment of the cooling
  tubes are all issues that need to be addressed.
• Possible cost risk ( 500.0 k )

Cooling plates and tubing
3
General Statement

• All of the options that have been and will be
  discussed are achievable. They are options that
  will solve the cooling requirements for the
  modular coils.
• All it takes is money and schedule
• The details and requirements for the latest
  cooling system will increase the installation
  time during winding.

4
Cooling Program Objective

• Objective Performance
• Provide the necessary cooling required to operate
  the modular coils
• Cooling system must incorporate dielectric breaks
  as required
• Objective Installation
• Hold costs and schedule
• Minimize the amount of on-line time required to
  install cooling system.
• Compare the modular coil fabrication activities
  to an automobile assembly line.
• Stage as many sub-assembly activities off-line.

5
Issues With Baseline

• Issues
• Dielectric break requirements
• Installation of outer chill plates
• Attachment of cooling lines?
• Working area- remember that installation of
  components is not performed on bench
• Minimize the number of small parts (rivets)
  potential for lost parts in coil
• More parts longer installation times
• Copper braid option Introduces risk of the
  copper strands penetrating insulation prior to VPI

6
Baseline Cooling Concept
cladding

• Requirements / constraints
• 15 minute cool-down
• copper is electrically isolated from tee
• No electrical continuity (loops) in copper parts
  in any direction
• No copper parts larger than 2 inches
• No electrical continuity through cooling tubing
• Fits in .08 inches laterally (not tube)
• Design
• Copper cladding, formed from flat developments,
  next to tee
• Copper chill plates on outside of winding pack
  connected to cladding
• Chill plates have electrical break
• Tubing brazed to copper strips
• Strips attached to chill plates

Cooling tube
chill plates
Electrical break
7
Inner Cladding Plates
Provide mating joint for plates

• Present design with vertical slits work well
• Easy installation
• Partially annealed, water-jet cut, pre-formed
  plates
• Complete cladding fitup in place

8
Cladding to Chill Plates

• Several options for connecting cladding to
  chill plates
• Brazing- damage insulation
• Tig welding- damage insulation
• Riveting- tested
• Staking- tested
• Dielectric Break
• Provide break using B-stage cryogenic insulation
• Appears to work
• -179 deg C to 149 degrees C (10 minutes) (no
  cryostat was used)
• More tests needed

-149 degrees C 124 degrees K
-179 degrees C 94.6 degrees K
9
Riveting Ends

• Will be difficult to install in place
• Too many loose parts
• Time consuming

10
Staking the Edge Connections

• Looks good. No real difficulties
• Fast efficient method
• No loose parts

11
Outer Chill Plates and Tubing

• Installation of outer cooling tubes needs
  additional work
• Pre-forming of cooing tube looks like good
  option.
• Brazing or soldering tube in-place would damage
  insulation.
• Pre-brazing to plates alignment of components
  very difficult.
• Attaching tubes with fasteners- real
  possibilities.

12
Mounting Cooling Tubes to Chill Plates
13
RD Activities

• RD activities performed
• Cladding to chill plate termination
• Dielectric break cladding to chill plate
• Cladding installation trials
• RD activities to be performed
• Outer chill plate installation
• Cooling tube to chill plates