Transcript Document

Status of infrastructure
Yury Ivanyushenkov
Applied Science Division,
Engineering and Instrumentation Department
RAL
MICE Video Conference, August 17, 2005
1
Scope
•
Magnetic shielding in the MICE hall
•
MICE hall preparations
•
Support system overview
•
Spectrometer solenoid support
2
Magnetic shielding in the MICE hall
3
MICE fringe fields: Problem
Magnetic field should not exceed 5
gauss in a public area (ISIS control
room).
Magnetic modelling predicts that
the 5 gauss line is outside the
MICE hall – passive shielding
may have to be used.
Volume in blue: 1000 gauss field
Volume in orange: 5 gauss field
4
Fringe fields: Passive magnetic shielding
20 mm
Flux lines from unshielded coils (MICE Stage 6)
r =4 m
Coil axis
2d axi-symmetric model of
iron shield
Flux lines from shielded coils
with a cylindrical,
10 mm thick steel shield,
D=10m.
5
Magnetic shielding: Thickness
Bmod (T)
Field detail in the shield region
for the different thickness of steel cylinder modelled.
0.0075
0.007
0.0065
0.006
0.0055
0.005
0.0045
0.004
0.0035
0.003
0.0025
0.002
0.0015
0.001
0.0005
0
No shielding
10mm
5mm
3mm
5 gauss
4.5
4.7
4.9
5.1
5.3
5.5
Field radially at Z=0 (m)
6
MICE magnetic shield: Models
By Jim Rochford
8m
20 mm
20 mm
8m
r =4 m
Coil axis
Coil axis
20 m
2d axi-symmetric model of
iron shield
3d rectangular model of
iron shield
8m
8m
20 mm
4m
20 mm
6m
Coil axis
20 m
2m
20 m
Coil axis
3d rectangular model of iron shield top half only
3d rectangular model of iron shield extended to ground level
7
MICE magnetic shields: Iron
25000
B(g)
20000
15000
10000
5000
0
0
500
1000
1500
2000
H(Oe)
BH curve for iron as used in the models
8
MICE magnetic shield: Complete rectangular shield
5 gauss line
3d model of complete rectangular shield Bpeak=0.67T
9
MICE magnetic shield: Half of a rectangular shield
5 gauss line
3d model of ½ a rectangular shield Bpeak=0.93T
10
MICE magnetic shield: Extended half of a rectangular shield
5 gauss line
3d model of a rectangular shield extending to floor Bpeak=0.82T
11
MICE magnetic shield: Peak field in shield
1
0.9
0.8
Bmod (T)
0.7
0.6
3d rectangular tube
3d 1/2 rectangular tube
3d rectangular tube extended to ground
2d cylindrical tube
0.5
0.4
0.3
0.2
0.1
0
3950
3960
3970
3980
3990
4000
4010
4020
4030
4040
4050
distance along x at y=1 z=1375 (mm)
Peak field in shield for different models
12
MICE magnetic shield: Effect on the axis field
8
With 20mm thick iron shield
No shield
Difference (gauss)
5
4
6
Field (T)
3
4
2
1
2
0
0
-1
-2
Difference (gauss)
6
-2
-3
-4
-4
0
1000
2000
3000
4000
5000
6000
Effect of the presence of the shield on the axis field
MICE Collaboration meeting @ Columbia, 14 June 2003
13
MICE magnetic shield: Forces
Top Fx=0,Fy=-1470,Fz=0
1470N
Sides
Fx=(+/-)1330,
Fy=-150,
Fz=0
1330N
150N
Y
Z
X
14
MICE magnetic shielding
Revised 3D model:
Open ended rectangular box model
20mm thick iron plate
+
Two 150mm thick iron plates
ID 40mm OD 3.6m
6m
2m
17m
5.6m
3.8m
15
MICE magnetic shielding
For 200Mev/c,
beta 43cm - mode
Fringe field on outer walls
200MeV/c beta 43cm
Shield components
Top+sides+detector
Top+sides
Sides+detector
No shielding
Outer surface of
ISIS injector wall
Bmod (g)
0.8
0.72
0.71
1.78
Outer surface of
Control room wall
Bmod (g)
2.23
2.33
2.39
12.5
16
MICE magnetic shield: Summary of modelling
• 2d and 3d models agree well
• Can effectively contain 5 gauss line within hall by using a
20mm thick rectangular shield.
• Initial calculations of the forces on the shield are small
• The field has a very small effect on the axis field
Next step:
- Create a realistic two-wall model of the shield based on the
MICE layout (see next slide) and the latest version of
MICE magnetic configuration;
- Check shielding efficiency ( wall thickness is a parameter).
17
MICE magnetic shielding layout
Magnetic shielding walls
18
MICE magnetic shielding layout
Magnetic shielding walls
19
Magnetic shielding in the MICE hall
Conclusion:
• Preliminary modelling suggests that passive shielding of
MICE will work.
• Modelling needs to be finalized.
• Magnetic shielding design needs to be completed.
20
MICE hall preparations
21
MICE phase I initial
22
MICE phase I final
23
MICE hall preparations: To-do list
1.
•
•
•
Floor levelling:
concrete plinth at the lower floor part of the building
fill up the cellar
floor extension frame over the trench
2. Beam line radiation shielding support over the trench.
3. Staircases modification:
• the staircase on the ISIS linac side of the building
• the staircase on the ISIS control room side
4. Holes in the roof and the north wall:
• in the roof – for ventilation ducts
• in the wall – for hydrogen vents
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MICE hall preparations: To-do list (2)
5.
•
•
•
Hydrogen system R&D area
hydrogen extract hood and vent lines
part of mezzanine floor
part of magnetic shielding wall
6. The rest of magnetic shielding walls.
7. Beam-line radiation shielding.
25
MICE hall preparations: Status and plans
•
General layout is completed.
• Discussion with RAL civil engineers has started
-> work will be done by the external company
•
Programme of hall modification is being prepared
26
Support system overview
27
Support structure – Layout and sequences
28
Support structure - Required rail positions
Rail positions of downstream detector for Stages IV &
V will overlap with final stage VI rail positions
MICE Stage IV
MICE Stage V
29
Support structure – Rail and Force transfer concept
Traverse in X on rail system to give location to
+/- 2mm
Jack from rail and position in x-y-z to survey
targets on vacuum vessel
Shim to blocking plates to locate in x-y-z and
react forces
Survey
Target
Magnetic force
Module
Beam Axis
Y
Z
X
Shim
Jacks
Rollers
Y support
location
Rails
Floor Plate
30
Support structure – Super-module
Module to module
joints to react
forces in Z
CC/RF module
with stiff
support
structure
31
Support structure – Rail-mounting concept
Platform moves on rails
Platform is jacked from
the rails
32
Support structure – Force transfer concept - Y
Shimming to react vertical forces
33
Support structure – Force transfer concept - Z
Shimming to react axial (Z) forces
34
MICE rail system
Rails
35
Height of the beam in the MICE hall
Dia 650
Aperture in ISIS wall
1524*
1684.2
Support structure
160*
Concrete floor
36
MICE support structure - Module weights
Table from Wing
Module
Weight, kg
AFC module
1700
RF module
4636
Radiation shield
310
Tracker module
6650
(including 1200 kg
of magnetic shield)
Note: Table requires updating
Crane lifting capacity is
12 tonnes (two cranes joined)
or 8 tonnes (one crane)
37
MICE support structure – Next steps
• Revise support structure requirements/specs for full MICE
- include and analyze requirements of access to every module
( collect information from all technical supervisors)
Who is doing this ?
• Suggest support structure for Stage 2 (MICE phase 1)
(is it different from the one for complete MICE ?)
• Discuss revised version of support structure at RAL meeting
38
Spectrometer solenoid support
39
Spectrometer solenoid positions
Solenoid in the beam - position
Solenoid out the beam - position
40
Spectrometer solenoid support: Next steps
• Revise support structure requirements
- include and analyze requirements of access
( collect information from the technical supervisors)
Who is doing this?
• Suggest support structure for spectrometer solenoid at RAL
meeting
41
MICE module max height
Important: The max height from the bottom of the support frame to the top
of a module should not exceed 3200 mm
Concertina door
Concrete aperture
Hinged door
Max vertical
opening 3360 mm
Max horizontal opening 3200 mm
42