Post on 02-Feb-2016
description
transcript
Heinz Grote 1
Presentation to NSCXWENDELSTEIN 7-X Assembly
Max-Planck-Institut für PlasmaphysikKKS-Nr.:
1-ADDok-Kennz.:
-Txxxx.0Heinz Grote October 2007
Vacuum Systems at Wendelstein 7-X and Leak Testing during Assembly
Insulating vacuum in the cryostat
Ultra-high-vacuum in the plasma vessel
Interspace Vacuum system for multilayer bellows, double sealings, control coils, el. feedthroughs
Evacuation of the gas inlet into the plasma vessel – already working
Insulating vacuum in cryostats of the gyrotrons ECRH – already working
Vacuum system for pellet injection
Vacuum system and gas inlet NBI
Insulating vacuum ICRH
Vacuum systems for diagnostics (many)
Vacuum system for the cooling machine...
Heinz Grote 2
Max-Planck-Institut für Plasmaphysik, EURATOM Association
Leak testing Strategy
All components to be assembled are leak tested with Helium or SF6
-before delivery (qualification of the workshops varies)-during incoming inspection-after re-work-on the assembly stands immediately after welding or mounting of the sealings-finally in an integral leak test after closing the cryostat and the plasma vessel
Where ever possible pressure gradients during testing are equal as in working condition
Where ever possible tubes and weldings of cryogenic parts are tested at temperature of LN2
Heinz Grote 3
Max-Planck-Institut für Plasmaphysik, EURATOM Association
Leak testing Equipment (1)
All large components are leak tested with Helium in a vacuum tank
Volume: 55 m³inner diameter: 4.900 mmmax. inner height : 3.150 mmmax. height of load (crane height): 2.600 mmmax. weight of load: 7.500 kgbase pressure (< 2*10-7 mbar empty tank) (< 3*10-5 mbar loaded with W7-X coil)double–O–ring seal [Viton] with interspace pumping26 CF-ports various sizepumps: 4 x 65m³/h rotary vane pumps, 2 x 1.000m³/h roots-pumps 2 x cold traps 2 x 1.000 l/s turbomolecular pumps,
used for W7-X coil Paschen tests, He-leak tests of superconductors and He-cooling tubes on coils, support structure etc.
Heinz Grote 4
Max-Planck-Institut für Plasmaphysik, EURATOM Association
Leak testing Equipment (2)
All joints and weldings are leak tested locally with special designed chambers or flexible bags
Variety of silicone sealed leak detection chambers made of stainless steel
Heinz Grote 5
Max-Planck-Institut für Plasmaphysik, EURATOM Association
Leak testing Equipment (3)
Leak detection chamber made of Al sealed with Tacky Tape
Heinz Grote 6
Max-Planck-Institut für Plasmaphysik, EURATOM Association
Leak testing Equipment (4)
Leak detection chamber made of stainless steel foil sealed with Tacky Tape
Heinz Grote 7
Max-Planck-Institut für Plasmaphysik, EURATOM Association
Leak testing Equipment (5)
Silicone sealed stainlesssteel chamber for assuring100 % He-atmosphereduring leak testing
Temperature sensor
He- service pipe
Data logger
Leak testing at 77 K
Heinz Grote 8
Max-Planck-Institut für Plasmaphysik, EURATOM Association
Mechanical Pumping System - Cryostat Requirements during pump down
Requirements during pump down from atmospheric pressure
Evacuation down to 1 mbar 24 hours
Evacuation down to 1*10-2 mbar 72 hours(from 1 down to 1*10-2 mbar in
48 hours)
Cooling down p < 1*10-2 mbar
Outgassing rate of the insulation 1*10-5 mbar*l/(s*m²)
Load of the insulation with water vapor 0.25 g/m²
Amount of the insulation 30 layers á 1,400 m² (conservative assumption)
Heinz Grote 9
Max-Planck-Institut für Plasmaphysik, EURATOM Association
Mechanical Pumping System - Cryostat Working requirements, Geometry
Working Requirements
Max. partial pressure (He) 1*10-5 mbar
Max. tolerable leak (He) 1*10-2 mbar*l/s Seff >= 1,000 l/s(inside the
cryostat)
1,000 l/s in the cryostat 2,000 l/s at the port 3,180 l/s
Geometry
Ports for pumping 3 per module (= 15 overall),diameter 500 mm each
Volume approx. 500 m³
Heinz Grote 10
Max-Planck-Institut für Plasmaphysik, EURATOM Association
Mechanical Pumping System - Cryostat Layout
Pumping set on each of the 5 modules
Gate valve DN 320 ISO F
Tube DN 320, length 4 m Bypass DN 100
TMP 2,000 l/s
Rotary vane pump 65 m³/h
Roots pump 250 m³/h )) on 2 modules only
Rotary vane pump 65 m³/h )
Heinz Grote 11
Max-Planck-Institut für Plasmaphysik, EURATOM Association
Mechanical Pumping System - Cryostat Present status
Uwe Schultz
Heinz Grote 12
Max-Planck-Institut für Plasmaphysik, EURATOM AssociationPumping System for Plasma Vessel
- Base pressure, UHV-conditions, 10-8 mbar Turbomolecular pumps (TMP)
- Experimental, 10-5 - 10-4 mbar Hydrogen (Deuterium, Helium)
up to 10-3 mbar in the Divertor
high gas load Cryopumps,
TMP + Roots + Rotary-pumps
(3-stage mechanical pump system)
- Regeneration of Cryopumps with TMP
- Pumping through divertor gap: Cryopumps behind the target modules
TMP: 10 individual systems 1 in each divertor unitat the ports AEH and AEP
Heinz Grote 13
Max-Planck-Institut für Plasmaphysik, EURATOM Association
Pumping System for Plasma Vessel Requirements for the Pumping System
Experiment: 3*1021 s-1 1.5*1021 molecules*s-1 ~ 50 mbar*l/s
Pressure in Divertor: < 5*10-4 mbar Pumping speed: > 100*103 l/s
cryo pumps: 75*103 l/s for H2
TMP: 25*103 l/s for H2
Pump down: ca. 1,300 m² inner surface, (1,000 m² stainless steel, 300 m² carbon, B4C)
outgassing: 1*10-7 mbar*l/(s*m²) (SS), 1*10-6 mbar*l/(s*m²) (C, B4C),
total: 4*10-4 mbar*l/s
base pressure : < 1*10-8 mbar Pumping speed: > 40*103 l/s TMP only
Heinz Grote 14
Max-Planck-Institut für Plasmaphysik, EURATOM Association
Pumping System for Plasma Vessel Mechanical pumping system – Layout of 1 unit
Pumping gap 2,430 l/s 2,870 l/s
node: 3,200 l/s
2*1,850 l/s = 3,700 l/s
Pumping gap 1,340 l/s 1,460 l/s
1,850 l/s
Port AEH Port AEP
Total approx.: 37.7*10³ l/s
25*10³ l/s at the ports AEH alonenecessary for operation in the standard case, wherethe interaction zone of the plasma with the divertor targets is locatednear this port
Heinz Grote 15
Max-Planck-Institut für Plasmaphysik, EURATOM AssociationPumping System for Plasma Vessel
Location of the Ports
Pumping ports
Pumping ports
AEP
AEP
AEH
AEH
Heinz Grote 16
Max-Planck-Institut für Plasmaphysik, EURATOM Association
Pumping System for Interspace Vacuum Present status
38 rectangular and oval ports with multilayer bellows (Plasma Vessel) 1 – 100 mbarto be vented only if both the cryostat and the plasma vessel are vented
40 rectangular and oval ports with double sealings (Plasma Vessel) ~ 0.1 – 1 mbar to be vented together with the plasma vessel
146 cryostat ports with double sealings ~ 0.1 – 1 mbar
to be vented together with the cryostat
3 independent roughing vacuum systems – fivefold each according to W7-X modules(dry roughing pump, valve, measuring gauge, tubes to ports DN12-20)
10 control coils will have interspace vacuum to protect the plasma vessel from water leaks
14 electrical feedthroughs – not permanently pumped
Heinz Grote 17
Max-Planck-Institut für Plasmaphysik, EURATOM Association
Control Schematic for Pumping System W7-Xbased on SIMATIC S7-400
master programmable logic controllers
part components W7-X
Olaf Volzke
central main control
W7-X