Mechanical Engineering Design Review

1
Mechanical Engineering Design Review

• BL 4.0.3 ARPES Endstation

Derek Yegian, Jonathan Denlinger, Keith
Franck 4/18/2008
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Beamline 3D Layout
Monochromator
M322
M323
M302
M303
G301
G302
G302 (temp)
M321/M331
RIXS
Entrance slit
Gas Cell
Exit slit
M332
M333
ARPES
TOF
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Endstation Layout
M322
M323
RIXS
M332
M333
ARPES
44
TOF (2-bunch only)
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ARPES Phase 1 (Sept. Installation)
Beam
Fixed Spool
Sample rotation 2-part rotary
Analyzer Fixed, horizontal
Turntable Locked in place
5
Support Structures (a)

• Two independent supports
• A) Vertical load (2000 lbs) of chamber/analyzer
  carried through SKF spherical plain bearing on
  base plate

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Support Structures (b)

• Two independent supports
• B) Horizontal load and moments carried through
  six-strut assembly
• Minor vertical load of tabletop and ancillary
  structure

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Chamber Assembly (a)

• Vertical rotation Alignment

Goal Top chamber flange to rotate with 20
micron sphere of confusion (1) Turntable on top
plate -- turntable rests on angled surface of
cam bearings (2) Align bottom bushing to
turntable rotation axis using dial indicator
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Chamber Assembly (b)

• Vertical rotation Alignment

(3) Install pumping base and top chamber through
the turntable (4) Align top flange of chamber to
rotation axis for position and
perpendicularity - use dial indicator -
adjustment screws for tilt, radial
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Chamber Assembly (c)

• Vertical rotation Alignment

(5) Tighten bolts on bottom alignment plate (6)
Raise lower support bearing (still allows
chamber rotation) -- swivel self-aligning
bearing 30,000 lb. capacity -- leveling pad
vertical adjustment -- plan for 1 mm vertical
rise (chamber fiducialization) -- takes weight
off cam bearings / six strut support
assembly (7) Phase I Clamp chamber to base
plate (no rotation) -- keep lifted off cam
bearings
Tighten bolts
Raise feet by 1mm
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Chamber Port Accuracy

• CMM report

Goal Top chamber flange to rotate with lt10
micron axis of confusion (1) Top port alignment
to bottom flange -- center offset dx0.0067
dy0.0142 , dr0.0157 -- parallelism dz
24.375 dA 0.6 millirad (2) Intersection of
analyzer flange to vertical axis dz
-0.0185 (from design value of 9.0 below top
flange) -- not crucial align beam to analyzer
sample to beam dy -0.0076 (crucial for
polar rotation)
analyzer
analyzer
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Seismic Parameters
Center of gravity
Base Floor Bolting Pattern

• Floor survey
• 3 existing 1/2 HILTI (type HDI) shells do not
  affect new anchor locations
• No grade beam conflicts
• Add four new 1/2 HILTI (type HDI) expansion
  anchors on 48x44.
• Factor of safety
• 1.4 (w/o vacuum load)
• 1.3 (vacuum load)

Manipulator/Centiax 75 lbs _at_ 83.8
47
Rotary Seal 40 lbs _at_ 71.9
Analyzer 325 lbs _at_ 58 Off-axis 32 est.
Chamber 400 lbs _at_ 51.3
60
450 lbs _at_ 36.5
X
Struts 150 lbs _at_ 26
Pumping Tree 450 lbs _at_ 27
Wgt 3350 lbs. Height 25.5
IP 250 lbs _at_ 17.1 Off-axis 20
Weldment 1350 lbs _at_ 6.35
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Seismic Safety
(Following Engineering note AL0015)
Center of Gravity 3700 lbs at 28.6 from floor
(2.38 towards analyzer) Floor Anchoring use
new ½ HILTI HDI on 48 x 44 Allowable loads
Tension 2,374 lbs. / Shear 1,798 lbs.
min. lever distance from bolt to edge 46
Horizontal inertial load in earthquake as high
as 0.7 g acceleration x 3700 lbs. 2580
lbs. Tension load due to overturning worst
case leverage ratio 25 / 21.8 .62 pull-out
load on two anchors 2580x.62 1600
lbs. pull-out load (tension) per anchor 1600 /
2 800 lbs. Shear load due to sliding shear
load per anchor 2580 / 4 640 lbs. Safety
Factor 1/( (800/2374) (640/1798) ) 1.4 If
500 lbs of vacuum load added (equiv. 450 lbs
towards analyzer, 210 lbs perp. analyzer) Safety
Factor 1 / ( (3030.57/2/2374) (3030/4/1798))
1.3
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Top Rotary Seal

• Phase I vs Phase II

• (Phase I)
• Standard 2-part face seal (have in hand)
• -- APX design --gt LBNL --gt DV Manufacturing
  (fab)
• H1.81
• -- double-sided flange on bottom for clearance
  of top ports
• standard H0.87
• -- double-sided flange on top to match Phase II
  height
• custom H1.8535 (or 2 x 0.87 1.74?)
• Sum 4.53
• (Phase II)
• -- Custom 3-part radial seal H 4.53375
• -- bottom connects to rotatable chamber
  (analyzer polar angle)
• -- middle connects to fixed stand
• -- top connects to rotatable manipulator (sample
  polar angle)

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Analyzer Rotation

• Phase I vs Phase II

• (Phase I)
• -- rigid nipple
• -- analyzer in horizontal geometry (vertical
  slit)
• -- support bracket off of base plate
• -- increase rigidity to stand
• (Phase II)
• -- Custom high load 2-part radial seal
• -- Rotation for selection two orientations (not
  scanning)
• -- Slow rotation speed (factor for safety)
• -- Sliding contact of analyzer lens mu-metal
  with chamber mu-metal (?)

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Summary
Phase 1 (Sept. install) Fixed chamber and
analyzer Turntable installed but locked
down Assembly will require extensive
alignment Vertical load taken by spherical
bearing Phase 2 Need robotics safety review/plan
for motions Vacuum load preloads cam
bearings Seismic loading has a factor of safety
of 1.27 min. Redesign of analyzer mu-metal liner
may be needed