LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 1 /6n LARP Phase II Secondary Collimator...
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Transcript of LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 1 /6n LARP Phase II Secondary Collimator...
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 1 /6n
LARP Phase II Secondary Collimator RC-1
Mechanical Design Review
01/04/09
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 2 /6n
Introductory Statements
Your comments and/or questions are welcome at any time . There will also be time
at the end for an in-depth discussion of any and all aspects of our design.
Sub-title of this talk:
“The Rotatable Collimator from the inside out”
Basic format I hope to follow:
• Internal component detail (CAD models and photos of real pieces (RC-0 / RC-1)
• Fabrication photos of components of the RC-0 Jaw aka Heater Test Jaw.
• Fabrication photos of some of the RC-1 components that are currently in work.
• Specifications and physics requirements and how we meet them.
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 3 /6n
Collimator Jaw-Hub-Shaft Concept
Jaw heats up along the side facing the beam and lengthens causingeach end to deflect away from the beam and into the 2mm annular gapbetween the Shaft and the Jaw.The Jaw also swells a bit causing the Jaw face move towards the beam.
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 4 /6n
Some Calculations
Jaw heating and deflection characteristics for
Steady State (SS) and Transient (TR) conditions
Component SS TR units
Max jaw temp 70.6 224 C
Max deflection toward beam 105 236 μ m
Surface Sagitta 226 880 μ m
Effective length 0.67 0.33 m
Water temp rise 20.3 C
Water pressure drop 2.4 bar
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 5 /6n
Cutaway of Jaw Assembly
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 6 /6n
RC-1 Half Shaft and Hub Assembly
Inner Keeper RingForces moly inner fingers to keep up with Glidcop expansion during brazing
Outer Keeper RingKeeps moly outer finger tipsfrom splaying out and away from Glidcop during brazing
Cu-Au alloybraze wire
This Outer Keeper Ringis machined off after brazing in order for Shaftto pass through Mandrel ID
This Outer KeeperRing acts as a stop to position the Shaftlongitudinally
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 7 /6n
RC-1 Molybdenum Shafts
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 8 /6n
Details of Ends of Molybdenum Half Shaft
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 9 /6n
RC-1 Hollow Glidcop Hub (prior to Cu plating & grooving)
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 10 /6n
Grooving details of Glidcop Hub
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 11 /6n
RC-0 Half Shaft and Half Hub Brazing
The two Half Hubs are now one. We originallyneeded to machine outa copper inner keeper plugthat forced the molyfingers out with the Glidcop during brazingto provide an opening for the tubing.RC-1 uses a thinner SSTring that can remain inside the Shaft with room for the tubes to passthrough.
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 12 /6n
Mandrel with Cooling Tube
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 13 /6n
RC-0 Mandrel at QC
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 14 /6n
RC-1 Mandrel in work
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 15 /6n
RC-1 Mandrel almost finished (March 15th)
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 16 /6n
Completed RC-1 Mandrel March 25th
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 17 /6n
No Vacuum to Water Joints
Tubing is wound into Mandrel groove while free ends pass through the hollow center parallel to each other yet exiting on Shaft centerline. When Collimator rotates the tubes twist on their own axis but not around each other.
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 18 /6n
Tubing coil on turntable for winding
16m of tubing are removed from “loose coils”UHV cleaned and placed on a turntable for payout.
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 19 /6n
Winding tubing on the RC-0 Mandrel
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 20 /6n
Nearing the end or… forming the bend
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 21 /6n
RC-0 Mandrel Brazing Setup
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 22 /6n
Machining the RC-0 Mandrel to size
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 23 /6n
Collimator Jaw Brazed to Mandrel
•RC-1 Jaw has 5 cylindrical sections.•End sections are tapered.•RC-0 has 16 quarter sections, none are tapered.•The RC-0 Jaw to Mandrel fit up for brazing was quite time consuming & expensive.•Each quarter section had to be reworked to fit Mandrel final diameter!•Changing to full cylinders, to save time & cost, meant they should be a somewhat shorter to be easier to slide over the Mandrel with the tight brazing tolerances.•Robustness test will use 1 RC-0 and 1 RC-1 style Jaw
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 24 /6n
16 Jaw Quarters with Cu/Au alloy foils
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 25 /6n
Jaw Braze preps continue
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 26 /6n
RC-0 Jaw Brazing Success
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 27 /6n
RC-1 Jaw braze Assembly
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 28 /6n
Section of Revised Jaw
Cu-Au braze wirego here ~ 40 snaprings
Braze wires replace foils simplifyingbraze preps
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 29 /6n
RC-1 Final Machining
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 30 /6n
20 Facets 20 years?
20.25mm
Thickness of Glidcop Jaw (facet to water) is 24.5mm.
~15 degree taper at each end places RF contact bearings ~10mm away from facet.Facet length = 930mm (oal) – 2x38mm (taper) = 854mmTaper may be too generous and could be shortened for a longer facet.
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 31 /6n
Facet Flatness
Flatness Specification is 25 microns over full length of Jaw.
– How did we do?• Generally very good (4 of 5 facets checked met spec).
• Worst facet has a sagitta of 43 microns.
– How we will do even better!
• Newer milling machine.
– Competitive bid with specification of 25 micron rather than “best effort”
• May suggest vendor perform test mill of dummy piece to qualify process prior to fab.
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 32 /6n
Jaw Facet Preliminary measurement for end-to- end flatness
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 33 /6n
Measuring RC-0 Jaw facet flatness
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 34 /6n
Link to RC-0 Facet Flatness data
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 35 /6n
Up Beam end Jaw Support Version 1
Diaphragm allows Jaw end-to-end offset and Shaft sag.Flex vanes compensate (along with the diaphragm) for Shaft expansion
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 36 /6n
Jaw Support Development
A few thoughts:
Rigid mount would hold drive gearing in alignment with Shaft.This would require a flexible connection to the shaft to allow for deflection (sag)
due to gravity and Jaw end-to-end offset.Or a spherical bearing. At the time we were unable to locate a full complement
ceramic spherical bearing set.So… A diaphragm was introduced to attach the gear to the Shaft.This diaphragm, if designed correctly, should be able to distort not only for the
angles but also for the change in length of the Shaft due to thermal effects. Eventually it was determined that the End Support would need to flex to help the
diaphragm absorb the longitudinal expansion. Version 1 was designed.Finally the current version combines the diaphragm angular distortions with the
flexibility of the original End Support.The final hurdle is to find an acceptable high strength stainless steel to fabricate
it from. (Restrictions may eliminate some H.S. stainless steels which contain Co as an alloying element).
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 37 /6n
Up Beam Jaw Support Current Version
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 38 /6n
Down Beam Jaw Support Current Version
100 1 mm dia. ceramic ball bearings roll betweenthese two races
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 39 /6n
Cutaway of Jam Nut and Support
Jam Nuts mate at beveled surfaces to strengthen tip of Support
Rotation Mechanism mountsto tab on bearing race
100 1mm dia. Ball bearings roll in “V” groove
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 40 /6n
Outboard Bearing Race/Axle
Buttress Threads
100 1mm ceramicball bearings roll here
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 41 /6n
Inboard Bearing Race w/gear Drive mounting tab
Bearings roll here
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 42 /6n
Jam Nut
Two of these lock Collimator Jaw to the End Support
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 43 /6n
Shaft Ends are grooved for ceramic ball bearings
Ceramic bearings roll here and at far end
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 44 /6n
Shaft End bearing groove details
Bearings roll here
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 45 /6n
Jaw End Support System w/cooling tube
(Bellows removed to show support detail)
Flexible support is high strength stainless steelwelded to bottom ofbellows cuff at assembly to Tank Base Plate
Jaw Shaft End rests in slot of Support and is held by jam nuts on either side
~100 1mm dia. ball bearings in End adapter for rotation
Bellows mounting to Drive is unchanged from CERN design
Cooling tube adapter is tig welded after Jaw is installed in Tank
“Beefed-up” design still permits Jaw end-to-end offsets (3mm), Shaft thermal expansion and static sag. Deflection is improved for non-horizontal collimator positions.
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 46 /6n
Jaw Rotator/Gear Drive Accuracy
Jaw face alignment specification dictates an indexing type of mechanism. This drive allows up to 8 mis-counts of drive motor steps before Jaw moves off position.
2x1 bevel reduction in combination with 80 x1 worm reduces side load on drive and support to a minimum level.
Worm also provides locking of Jaw.Backlash is a minimized due to tubing
torque load
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 47 /6n
Indexing the Collimator Jaw
Indexing can be 1 facet, 5 facets for 90 degrees, 10 facets for 180 degrees.
For a distortion of Jaw in the plane of the beam a 90 degree advance would render the distortion a non-problem.
After a 180 degree advance a subsequent hit might correct the distortion, if a were of the same magnitude.
Following a sequence of 10 facets (180 degrees), 1 facet then 10 facets, a total of 5.25 twists of the tubing would be needed to “use up” all 20 facets.
Tubing was twisted an equivalent of 8 times. No visible defects observed.
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 48 /6n
Twisted Hollow Copper 10mm x 7mm
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 49 /6n
Ratchet actuation conceptual arrangement
Hammer contactshere duringover-travel of Jaw
Wire Springs restore Hammer after ratchet movement
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 50 /6n
Jaw End Details for Image Current connection
300 Rhodium Plated stainless steel ball bearings roll here
Bearing racesfit in recesshere
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 51 /6n
Image Current Bearing Race (example)
GlidcopRing details are similar for both races
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 52 /6n
Image Current Foil Assembly Version 1
Height of parts was necessary to shadow the Gear Drive on top of Jaw End Support
This surface mounts to bearing race
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 53 /6n
Current Version of Foil Assembly
Temp sensor mounts here
Reduced heightof foil is minimum to shadow “Geneva”
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 54 /6n
Temperature Sensor/ Image Current Foil mount
Foil Brazes Here
Temp Sensor mounts here
Mounts to Bearing Racehere
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 55 /6n
Current Version of Image Current Foil
1mm x 40mm Glidcop foil will be life cycle deflection tested
This end curves to conforms to Mountfor brazing
This end curves toconform and attachesto Beam pipe Flange ID
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 56 /6n
Preliminary Tank concept
First transition from roundpipe to square geometry is machinedinto the flange end of tank. Flexible Glidcopfoils (not shown) carry image current to second transition which tapers meet Jaw end.
Tank has tapered featuresto prevent upsetting the image current
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 57 /6n
Why the change?
We were interested in the ability to work on the image current components after things were welded up because we may not get it right the first time.
Results from preliminary laboratory RF tests showed that geometry to be less an issue than previously anticipated so the more complicated transitions may not be needed.
We will be hand tig welding the tank together rather than e-beam welding so distortion could be less of an issue.
Pluses:Uses standard pipe.Thinner wall results in less radiation effects.Camera ports for viewing the Jaw face remotely seem a bit simpler to implement.
Minuses:However, HOM modeling has recently shown high heating loads (larger volume).Until those issues are resolved this configuration might only be useful for the
TT60 tests.
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 58 /6n
New Cylindrical Tank Concept
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 59 /6n
Cylindrical Tank body
Tank is 355.6mm diameter x 6.35mm wall welded pipeMaterial is 304 SST. Note: Weld seam will be eliminated by cutout at bottom.
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 60 /6n
Base Plate
Base Plate is only slightly larger than CERN design
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 61 /6n
End Flange
Tank End Adapter reduces the Tank dia to a DN250 CF FlangeMaterial is 304LN, if required, otherwise 304L
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 62 /6n
Beam Pipe Adapter
End Flange reduces the DN250 CF Flange to DN100 Beam pipe FlangeMaterial is 304LN, if required, otherwise 304L.Note: Small hole is for the Camera Viewport Nipple
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 63 /6n
Assembling the Tank for welding
End Flanges could be tackwelded to cylinder first
Fixturing holds Cylinder rigidTo retain shape during welding
Collimators were previously assembled to Base Plate and welded into bellows end cuff
All viewports are previously welded in
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 64 /6n
Proposed TT60 Robustness Test Configuration
• Preferred orientation is 0 degrees.• RC-0 & RC-1 Jaws are used.• Collimator mounts on CERN stand.
– Cooling water quick connect?– Cables do not?
• Laser micrometers mount herefor measuring possible permanentdistortion after beam strike
• End ports are 1mm thick titanium.
• Vacuum pump (if needed) mounts to tee at down beam end.
• Chain tensioners used on all flanges.
Cameras mount here (both ends) for remote viewing surface damage to RC-1 Jaw after beam strike
Beam
DN250 flanges at ends permit access prior to test and after “cool-down period”
LARP LHC PHASE II COLL RC1 - S. Lundgren 1 April 2009 No 65 /6n
Bonus Slide