TQS

1
TQS Progress and plans

• Shlomo Caspi
• LBNL
• Collaboration meeting
• FNAL
• April 18-20 2007

2
Outline

• Test results of TQS01, TQS01b, TQS01c
• Training and short sample performance
• Measured strain-stress
• Comparing magnet results
• TQS02a test preparation
• Final assembly April 2007
• Test in early May at FNAL MTF

3
Coils and Pads subassembly
4
TQS01 Final assembly

• Two Subassemblies
• Structure pack shell and yoke
• Coil pack coils and pads

5
Key and bladder assembly

• Assembly Procedure
• Coil pack snug inside structure
• Axial pre-compression 250 kN/end
• Azimuthal coil pre-compression -15 MPa
• Cool-down
• A factor 10 gain in azimuthal compression (150
  MPa)
• A factor 3 gain in applied axial compression
  (750 kN)
• Controlled and predictable applied stress based
  on analysis

6
TQS01 summary ..
TQS01 TQS01b TQS01c
Coils 5,6,7,8 7,8,14,15 5,7,8,15
Island Bronze Bronze Bronze (pinned)
Slip planes no yes yes
Conductor MJR MJR MJR
Pre-stress Axial Azimuthal Cool-down Axial Azimuthal Cool-down Axial Azimuthal Cool-down
Test 4.4K (LBNL) 4.4K (LBNL) 4.4K, 1.9K, FNAL
Mag. measurement no no yes
7
TQS01 measured .
TQS01 TQS01b TQS01c
Maximum current (A) 10602 (4.4K) 11019 (3.2K) 9932 (4.4K) 9570 (4.4K) 10521(1.9K) 9989 (4.4K)
Iss () 87 (4.4K) 82 (4.4K) 80-82 (4.4K) 80 (1.9K)
Shell cold (MPa) -t 152 158 142
Shell cold (MPa) -z 143 140 137
Rods cold (MPa) -z 113 116 148
Island cold (MPa) -t -198 -202 -162
Island cold (MPa) -z 34 34 39
Coil calculated cold (Sigma-t, Sigma-z) (MPa) -150, 12
8
TQS-01,01b,01c training .
4.4K
9
TQS-01,01b,01c training
10
TQS01/01b Quench-Origin
Majority of quenches originated near island gaps
11
TQS01c Quench-Origin
12
Magnetic measurements - TQS01c
13
TQS01 Transfer Function
14
Measured Gradient
15
TQS01 Normal harmonic b6
16
Shell Azimuthal stress
17
Shell Axial stress
18
Rods Axial stress
19
Island Azimuthal stress
20
Island Axial stress
21
Strain measurements

• Structure
• Azimuthal and axial gauges on the shell
• Axial gauges on the rods
• Coils
• Azimuthal and axial gauges on the inner islands
  (center)
• Axial gauges on the inner islands (magnet ends)
• Azimuthal gauges on the coil to calibrate against
  bronze island (TQS01b)
• Axial gauges on the coil to measure differential
  strain near island gap (TQS01b)

22
Structure Strain Gauge

• Shell
• 4 azimuthal and 4 axial
• Rods
• 4 axial

23
Island Strain Gauges
24
Coil Gauges
Azimuthal gauges
Gap- No Gap axial bridge
25
TQS01b - Shell
26
Rod (TQS01b)
27
Island Center (TQS01b)
28
Island average stress during excitation (TQS01)
I10.6 kA
29
IslandCenter_Y
30
IslandCenter_Z
31
Island_YZ_Stress
fixed axial strain reduced azimuthal strain
increase axial stress
32
Coil 15_YZ_Stress
33
MIITs study current response (TQS01c)

• MIITs in coil 15

34
MIITs study - stress response (TQS01c)
35
Coil05_YZ_Stress
36
Coil 15 TQS01c
37
MIITs study - Coil 7 (TQS01c)
38
TQS-CW-015_Sample-3_Lead-End
39
Temperature compensator - free_Bronze
40
Temperature compensator - free_Bronze
41
Layer 2 OD (TQS01b post test)
No visible cracks
42
Layer 1 OD (TQS01b post test)
No visible cracks
Layer 2 islands removed
43
Layer 1 ID (TQS01b post test)
No visible cracks
44
Coil 9 ID post test (TQC01)
Directional cracks
bubbles
45
TQS01c straights post test
46
TQS01c ends post test(no bubbles)
47
TQS01c post test
48
TQS02

• Same structure as TQS01
• 4 new coils (new conductor- RRP)
• New islands (Ti replacing Bronze)
• Inner layer islands pinned to outer layer
• Similar assembly procedure

49
Scan of axial-strain along coil turn 1
50
Coil strain near a gap (TQS01b)
A bridge measures strain concentration in the
coil as a result of a segmented island
51
Island-C15-Zgap-bridge
Training
Cool-down
Warm-up
Assembly
300K
52
TQS 01/02 calculated Strain/Stress at 4.4K
Bronze - with axial support Titanium- with axial support Titanium- no axial support
Island Strain µe? -1900 -750 -880
Island Strain µez 760 -520 -180
Island Stress s? -215 -129 -135
Island Stress sz 25 -105 -65
Coil Strain µe? -3300 -3100 -3240
Coil Strain µez 1000 1000 1400
Coil Stress s? -150 -130 -129
Coil Stress sz 12 30 44
53
Reacted coils with Ti Islands
54
TQS02 Reacted lead side
55
TQS02 Reacted return side
56
Titanium island

• Mechanical stored energy reduced by factor 2-3
• Gaps between segmented islands closed
• Slightly higher axial tension in the coil
• Slightly lower azimuthal stress in the coil
• Possible removal of axial rods

57
Summary

• A structure with axial and azimuthal pre-stress
  control
• low assembly pre-stress
• substantial pre-stress gain during cool-down
• TQS01,b,c reached a plateau of 80-87
• All Islands are in axial tension
• Epoxy cracking in islands gaps
• Strain concentration in turn 1 near gaps
  (measured and calculated)
• Most quench origins are near island gaps
• No evidence of separation or epoxy cracking near
  the ends
• Importance of strain gauges and understanding
  their complexity
• Coils can experience high stress and maintain
  their integrity.
• Negligible impact of Lorentz forces on structure
• Analysis and expectations - measurements and
  confirmation

58
Summary continue

• Reversibility coils and structure can return to
  their initial warm stress condition
• Evidence of coil sensitivity to strain
• Spot heaters to calibrate coils before and after
  training
• Ti islands with no gaps during reaction and
  impregnation