Vacuum design, interventions and operation in radioactive environment Jose A. Ferreira on behalf of TE-VSC CERN experience: Vide en milieux ionisants, 22-24 noviembre 2017, GANIL 1 Contributions from Pawel Krakowski, Robin Nelen, Jaime Perez Espinos and Lukasz Piotr Krzempek
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Vacuum design, interventions and
operation in radioactive
environmentJose A. Ferreira on behalf of TE-VSC
CERN experience:
Vide en milieux ionisants, 22-24
noviembre 2017, GANIL1
Contributions from Pawel Krakowski, Robin Nelen, Jaime Perez Espinos and Lukasz Piotr Krzempek
Outline
Vide en milieux ionisants, 22-24
noviembre 2017, GANIL2
• Material validation
• Reduce exposure
• Tooling
• Remote handling
Vacuum design of radioactive areas
• Preparation
• Dose planning
• Tooling and training
• Execution
Interventions in radioactive areas
• RIBs operation: ISOLDE
• New RIBs facility: MEDICIS
Operation of radioactively contaminated areas
Outline
Vide en milieux ionisants, 22-24
noviembre 2017, GANIL3
• Material validation
• Reduce exposure
• Tooling
• Remote handling
Vacuum design of radioactive areas
• Preparation
• Dose planning
• Tooling and training
• Execution
Interventions in radioactive areas
• RIBs operation: ISOLDE
• New RIBs facility: MEDICIS
Operation of radioactively contaminated areas
Design: Material Validation
Why?
Consequences of equipment
radiation damage :
• Machine unavailability
• Unforeseen replacement
costs
Equipment qualification allows :
• Meeting equipment lifetime
and specs
• Anticipate failures
Vide en milieux ionisants, 22-24
noviembre 2017, GANIL4
Vacuum bake out jacket irradiation with
gamma up to 10 MGy is heavily damaged
Design: Material ValidationCERN has a tested and extensive compilation of radiation test data: “Yellow books”
Late 70’s - early 2000’s :
Yellow books: Compilation of radiation damage test data
Current situation
Increasing demand for high dose irradiation tests
Equipment owner fully responsible for their equipment
R2E and R2M
Vide en milieux ionisants, 22-24
noviembre 2017, GANIL5
Yellow book report CERN-98-01
Compilation of radiation damage test data
http://cds.cern.ch/record/357576
Design: Material Validation
Vide en milieux ionisants, 22-24
noviembre 2017, GANIL6
Preparation
Material(s):
Representative radiation (Gamma, Particles)
Installation area(s) and
expected lifetime:Total dose /
fluency
Pre- and Post-Irradiation
characterization test(s):
Samples size / shape / number
RequirementsChoice of an
irradiation facility
The sub-WP1 (R2E):
• Task 1: Active gauges in the arcs;
• Task 1.2: Active piezo gauges in the arcs & dump lines;
• Task 2: Active gauges in the LSS;
• Task 3: 24 VDC local power supply for fixed pumping groups.
• Radiation Hardness Guideline for VSC electronics developments for 500 Gy
Design: Material Validation
Vide en milieux ionisants, 22-24
noviembre 2017, GANIL7
LOG#1LOG#2 4-20 mA
Vac sim 11TΩ
The sub-WP2 (R2M):
• Task 1: O-ring seals;
• Task 1.2: F6 and F14 O-ring seals under compression; (Awaiting
for irradiation)
• Task 2: Permanent bake-out components;
• Task 2.2: New bake-out jackets for LHC bellows close to
collimators;
(Awaiting for irradiation)
• Task 3: NiTiNb SMA (Shape Memory Alloy) connectors;
• Task 3.2: SMA (Shape Memory Alloy) connectors set-up in
TDC2;
• Task 3.3: 4 SMA set-ups in TDC2 with pumping and online
monitoring (Just approved!)
• Task 4: Primary and turbo pumps;
• Task 5: Micro switches and distributors for sector valves;
• Task 6: Passive penning gauge and its HV cable under high
HEH;
• Task 6.2: Induced current in HV cables under radiation;
• Task 6.3: Radiation induced cables aging impact on their
electrical performance
(all samples irradiated, awaiting for post studies);
• Task 7: Silicon rubbers and polyurethanes clamps, vacseal &
epoxies;
• Task 8: Piezoelectric venting valve;
• Task 9: Passive piezo resistive gauge in the LSS & dump lines.
Design: Material Validation
Vide en milieux ionisants, 22-24
noviembre 2017, GANIL8
Immediate pressure change when
beam ONImmediate pressure change when
beam ON or OFF
When no beam pressure values
come back to previous states !
No memory effect…
BEAM OFF
BEAM ONBEAM ON
BEAM OFF BEAM OFF
BEAM ON
4E-10 mbar
6E-11 mbar
~E-12 mbar
RUN_2 and 3 have confirmed that the TFA3 Triaxial cable is the source of “spikes”
RUN_2 and 3 only 3 penning gauges and 1 simulator
Gaugea2
disconnected
and replaced by
passive simulator
(11 TΩ)
RUN_1 only penning gauges
4 passive penning
connected to small
vacuum chambers
pumped down in
ranges from 10-10
up to 10-12 mbar
The same behaviour
was observed with
gauge and passive
vacuum simulator !
Outline
Vide en milieux ionisants, 22-24
noviembre 2017, GANIL9
• Material validation
• Reduce exposure
• Tooling
• Remote handling
Vacuum design of radioactive areas
• Preparation
• Dose planning
• Tooling and training
• Execution
Interventions in radioactive areas
• RIBs operation: ISOLDE
• New RIBs facility: MEDICIS
Operation of radioactively contaminated areas
Design: Reduce exposure
Vide en milieux ionisants, 22-24
noviembre 2017, GANIL10
1970 quick connect clamp
developed for PSB:
Low cost seal
Quick installation and
removal
Low activation (aluminium)
Extreme reliability for UHV
Space allowed along beam
axis for joint including
clearance <40 mm
Small radial space occupied
by the quick connect
Option to be electrically
insulated
Mild bake-out 130°C
PS195 clamp (quick connect up to 150 mm)
Low Cost Vacuum Hardware Developed for the CERN PS Booster
C.E. Rufer and W. Unterlerchner
IEEE Transactions on Nuclear Science Vol 18-3, June 1971
Design: Reduce exposure
Vide en milieux ionisants, 22-24
noviembre 2017, GANIL
11
PS195 clamp was extremely successful Other designs followed during 70’s
PS250 (up to 200 mm tube)
SPS collars:
Tube up to 70, 159, 219,
273 mm
Bakeable up to 150°C for
D70 and DN159, 80°C for
bigger sizes
Design: Reduce exposureShape Memory Alloys
No seal
Open/close by heating/cooling
Vide en milieux ionisants, 22-24
noviembre 2017, GANIL12
Proof of concept of SMA connectors for
Ultra High Vacuum (UHV) chambers.
T<As (40 °C) T>Af (>100 °C)
pmax
SMA ring
Tube
1. Mounting at room temperature
2. Tightening by heating above 100 °C
3. Leak Rate < 10-10 mbar·l·s-1 at room temperature
4. Dismounting by cooling down to -40°C
Mounting Clamping
T = RT
pop
Operation
T<Mf (-40 °C)
Dismounting
As: Austenite start temperature Af: Austenite finish temperature Ms: Martensite start temperature Mf: Martensite finish temperature
Material properties:
NiTi based alloys
Magnetic permeability < 1.002
Thermal outgassing: < 10-13 mbar∙l∙s-1∙cm-2
Radiation hard ?? (tests ongoing)
Design: Reduce exposureShape Memory Alloys
No seal
Open/close by heating/cooling
Vide en milieux ionisants, 22-24
noviembre 2017, GANIL13
Proof of concept of SMA connectors for
Ultra High Vacuum (UHV) chambers.
T<As (40 °C) T>Af (>100 °C)
pmax
SMA ring
Tube
1. Mounting at room temperature
2. Tightening by heating above 100 °C
3. Leak Rate < 10-10 mbar·l·s-1 at room temperature
4. Dismounting by cooling down to -40°C
Mounting Clamping
T = RT
pop
Operation
T<Mf (-40 °C)
Dismounting
As: Austenite start temperature Af: Austenite finish temperature Ms: Martensite start temperature Mf: Martensite finish temperature
Material properties:
NiTi based alloys
Magnetic permeability < 1.002
Thermal outgassing: < 10-13 mbar∙l∙s-1∙cm-2
Radiation hard ?? (tests ongoing)
A compact, leak tight and easily mountable/dismountable connection system
Possibility of remote controlling
Possibility to use in high demanding areas (e.g. collimator areas,
machine/detector interface)
Possibility to use in limited access spaces
Possibility to connect dissimilar materials
Outline
Vide en milieux ionisants, 22-24
noviembre 2017, GANIL14
• Material validation
• Reduce exposure
• Tooling
• Remote handling
Vacuum design of radioactive areas
• Preparation
• Dose planning
• Tooling and training
• Execution
Interventions in radioactive areas
• RIBs operation: ISOLDE
• New RIBs facility: MEDICIS
Operation of radioactively contaminated areas
Design: Tooling
Vide en milieux ionisants, 22-24
noviembre 2017, GANIL15
1979 SPS clamp for remote handling: Two sizes DN159