Transcript Trip Report from CERN and Wendelstein W7-X.ppt

Trip Report from CERN and
Wendelstein W7-X
October 6 – 13, 2007
Michael Viola; Steve Raftopoulos; Bill Sands
October 6-10 CERN Geneva, Switzerland
October 10-13 Wendelstein W7-X, Greifswald Germany
CERN
Paparazzi Metrology
– “Bill Sands”
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Discussed Metrology
Met with Christian Lasseur and Raphael Goudard
– Photogrammetry improves with increased number of
pictures taken with less than 60 degree field of view
– Should fill Frame with target but not to edge
– Must cover at least 10 pixels of the CCD
– Should turn camera on side and upside down often to
allow software to compensate aberation errors.
– Should take absolute minimum of 9 photos
– Should have 1/3 overlap
– Distance between camera stations 2/3 of the
recorded distance
– If b = 2/3 * 2.8 * 2.1 then uncertainty ~ 0.060 mm
• Best achievable is .23 mm (offset of .019 mm)
– Choice of reflectors center sizes 12, 15, 40 mm
Metrology
Metrology
Metrology
Metrology
Metrology
CERN
• Discussed Welding
– Met with three: Gil, Stefano,
Michelle
– MIG is far better for distortion
– Weld from center to outside of each
stringer
– Weld alternate from center then left
right; right left
CERN
• Discussed Welding
– An example of a 10mm plate
is to the left with three
passes of MIG.
• Note little distortion and
excellent fusion
CMS
CMS
W7- X Welding
W7- X Welding
W7- X Welding
W7- X Welding
Wendelstein W7-X Welding
Welding
• Equipment
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Procedure
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MIG with active CO2 cooling of surface
NEW patented narrow gap weld tip for MIG
PT Drive improves feed
Weld from center to outside
Alternate from center out
Narrow GAP technique
Adjust weld to allow for narrow gap head
Comments
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Our TIG procedure:
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Way too many passes as a result of too small wire
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.4mm (3/32”) = 7 passes
Should use 1.6 mm wire = 3 passes (much less heat)
Check opportunity for pre-deforming or clamping
along longitude if possible
Distortion realized is >75% from root weld and
complete when 50% of weld is finished
Wendelstein W7-X Welding
Welding Recommendations
• Equipment
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Procedure
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MIG with active CO2 cooling of surface
PT Drive improves feed
NEW patented narrow gap weld tip for MIG
Weld from center to outside
Alternate from center out
Narrow GAP technique
Adjust weld to allow for narrow gap head
Comments
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Use very experienced and well qualified welders.
It takes two 3 week periods to qualify even a good
welder to perform reasonable Stainless steel MIG
welds.
Distortion realized is >75% from root weld and
complete when 50% of weld is finished
Welds configuration must be qualified with samples
and pull tests
6 mm
5 mm
11
mm
Wendelstein W7-X Metrology
• Photogrammetry
– Torsten, head of W7-X metrology
and Bob Brade head of JET
metrology.
– Presentation compares difference
between LTD and Photo
• LTD
– R=40 m
– ADM provides 10 microns + 50
microns
– No loss for ADM really since
encoders dominate error
• Photo
– R=5 m
– Uncertainty 0.2 mm
Wendelstein W7-X Metrology
• Laser Tracker
• Used for most of the
work
– Take three complete for
each measurement
• After scans they then pick
best one of the three to
use.
W7- X
W7- X Metrology
W7- X Metrology
W7- X Metrology
W7- X Metrology
W7- X Metrology
Wendelstein W7-X
NCSX Status review
General comments
• W7-X metrology grew in 2 ½ years
• Karl’s Assembly control division had three planners at top for
Status review
• Are shims qualified?
• Was flexibility of the coils a recent find?
• Having shims and bushings are overkill and raise cause for suspicion of design
and questions.
• Add the risk of tooling not working after commissioning
• Tooling for installing ports from underneath
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TF Coil installation and stability of field period assembly as we add components
TF and PF supports will likely cause distortion.
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can Ports be installed with vessel supports in place
How is it compensated?
Guys are so busy doing day to day tasks that there isn’t time to design the future
needs
The design of station 5 and 6 is of done so how can a review say confidently that
the design cost and schedule can be met?
Wendelstein W7-X
NCSX Status review
Status review
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Once you do a bottom up estimate, you must make milestones based on final date back
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Did we meet all milestones to date?
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Contracts
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All prototyping must use same materials; same configuration; same procedures
Have the design all been well defined (Stations 5 and 6) – wave of hand that it is just simple is not
enough
!!Station 5 and 6 are too rough!!
Talk about the risks in the technique and have a plan B
Understand all risky operations and have them accounted for.
A technical review needs to dissect the assembly steps
Formulate work to deal with remaining risky activities
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How long did it take to provide similar structures?
Why should review team believe that new contracts are shorter [sanity check of similar tasks.]
Design, material, interferences, schedule
Allow for repairs
Knoxville planning showed too many tasks in parallel responsible by same people.
Must also provide an explanation of plan B for either risky tasks OR not well defined work
If station 3,5,6 additional time were based on station 2 actual experience it would be more
convincing.
Allow for don’t know problems or missing designs
Promote pessimism