PEP-II Vacuum p1
New HER IR Vacuum ChambersNew HER IR Vacuum ChambersNew HER IR Vacuum ChambersNew HER IR Vacuum Chambers
Machine Advisory Committee MeetingMachine Advisory Committee MeetingDecember 14, 2004December 14, 2004
Presented by Rodd PopePresented by Rodd Pope
Machine Advisory Committee MeetingMachine Advisory Committee MeetingDecember 14, 2004December 14, 2004
Presented by Rodd PopePresented by Rodd Pope
PEP-II Vacuum p2
New HER IR VacuumNew HER IR VacuumChamber TeamChamber Team
Q4R/Q5R – Don Arnett & Albert ShengQ4R/Q5R – Don Arnett & Albert Sheng
Q4L/Q5L – Ted Osier & Rodd PopeQ4L/Q5L – Ted Osier & Rodd Pope
Q4/Q5 Bellows - Nadine Kurita & Manuel TrigosQ4/Q5 Bellows - Nadine Kurita & Manuel Trigos
Support from Ho DongSupport from Ho Dong
Managed by Nadine KuritaManaged by Nadine Kurita
PEP-II Vacuum p3
LocationLocation
BSC & Luminosity Stay ClearBSC & Luminosity Stay Clear
Synchrotron Radiation & Heat LoadingSynchrotron Radiation & Heat Loading
Beam Position MonitorsBeam Position Monitors
SupportsSupports HER Q4/Q5 Bellows Module
NEG Antechamber ScreenNEG Antechamber Screen
Design and FabricationDesign and Fabrication
Milestone ScheduleMilestone Schedule
OutlineOutline
PEP-II Vacuum p4
HER Q5L – Q4L & Q4R – Q5RHER Q5L – Q4L & Q4R – Q5R
PEP-II Vacuum p5
HER- Downstream, “Forward”, “Right”
HER- Upstream, “Backward”, “Left”
IPQ2RQ4RQ5RFrangible LinkHigh-Power Dump
IP Q2L Q4L Q5L Frangible Link
“Luminosity Chamber”
10MCollimator
19.5M
9.4M 8.4M5.7M
3.6M2.3M
2.3M3.6M
5.7M7.7M 8.5M 10.1M 11.4M
0.0 M
0.0 M
e-
PEP-II Vacuum p6
Design SpecificationDesign SpecificationBeam ParametersBeam Parameters
Maximum HER beam energy/current:Maximum HER beam energy/current: 9 GeV at 2.2 Amps “Farther Future” per M.
Sullivan
Maximum LER beam energy/current:Maximum LER beam energy/current: 3 GeV at 4.5 Amps
Beta *s for HER & LERBeta *s for HER & LER Beta x* = 28 cm
Beta y* = 7 mm “Farther Future” per M. Sullivan
Emittances for HER & LEREmittances for HER & LER Emittance x = 60 nm-rad
Emittance y = 24 nm-rad
PEP-II Vacuum p7
Beam Stay ClearBeam Stay Clear
Beam Stay-ClearBeam Stay-Clear HER BSC: +/- 12x x 9y
Luminosity Cone: 6.24
BSC through Q2R isBSC through Q2R is +/- 12x x 8.5y
Q2L Outboard FlangeLooking Toward IP12x x 9y BSC
6.24 Luminosity Cone
PEP-II Vacuum p8
Q4 HER BSCQ4 HER BSCOutboard Magnet End Looking Toward IPOutboard Magnet End Looking Toward IP
Q4L Q4R12x x 9y BSC
Luminosity Cone (6.24)~90% Clear
PEP-II Vacuum p9
Q5 HER BSCQ5 HER BSCOutboard Magnet End Looking Toward IPOutboard Magnet End Looking Toward IP
Q5L Q5R12x x 9y BSC
Luminosity Cone (6.24)~85% Clear
PEP-II Vacuum p10
Luminosity Clear RayLuminosity Clear Ray
BSC
Luminosity
Limiting Aperture is Frangible Link-Green Line Represents Clear Aperture-Green Line Clears Q5L & Q4L
Q5L Frangible Link LuminosityChamber
PEP-II Vacuum p11
SR, ISR, I22R & HOM Heat LoadsR & HOM Heat Loads
HER @ 9 GeV at 2.2 AmpsHER @ 9 GeV at 2.2 Amps
LER @ 3 GeV at 4.5 AmpsLER @ 3 GeV at 4.5 Amps
HOM & IHOM & I22R Engineering Guess = 269 W/mR Engineering Guess = 269 W/m Re-analyze at 1 kW/m (worst case estimate)
10% Reflected SR Power10% Reflected SR Power
PEP-II Vacuum p12
Heat Load SummaryHeat Load Summary
Q5R May Intercept B1L & B1R High Power SR Q5R May Intercept B1L & B1R High Power SR During Mis-steerDuring Mis-steer
Actively Safe Chamber (TC Interlocked)
Uniform Heating from HOM and I2R Loads
Balanced Cooling to Minimize Dynamic (Thermal) Bowing
Q5L & Q4L Intercepts B3, B2 & BLF HER SRQ5L & Q4L Intercepts B3, B2 & BLF HER SR Distribute SR Power Over H20 Cooled, Aluminum Chamber Wall
Distributed Masks Allow Larger BSC than Discrete Masks
Balanced Cooling to Minimize Dynamic (Thermal) Bowing
PEP-II Vacuum p13
Q4R SR Ray Tracing
Looking Toward the IP
e-
•Q4R is clear.
Q4R
PEP-II Vacuum p14
Q5R Beam Missteering Location
65 inches
e-
Q5R
B1 SRLooking upbeam
•Add additional cooling channels to eliminate uncertainty of HOM induced thermal gradient within missteering region.
•It is the worst case when B1 (R) and B1 (L) SR strike at the same spot.
•Active safe when using thermocouple to detect transient temperature rise.
PEP-II Vacuum p15
Locations of Thermocouples
Possible missteering area Combined 0.5 mrad horizontal and 1 mrad
vertical mis-steering.
B1(L)
B1( R)
Looking upbeam
Water channel
Water channel
Thermocouples, 1/8” deep,
3/8” equal spacing
PEP-II Vacuum p16
Transient Analysis due to Beam Missteering
PEP-II Vacuum p17
Transient Analysis due to Beam Missteering
Trip stress = 25ksidTmax = 97 C
Trip stress = 30ksidTmax=116 C
dT at thermocouple = 14 C
dT at thermocouple = 30 C
PEP-II Vacuum p18
LER SR Into Q4L HERLER SR Into Q4L HER
LER SR Thru Q4L IBF(0.5 mrad horizontal & 1.0 mrad vertical mis-steer)
-36
-26
-16
-6
4
14
24
34
-10 0 10 20 30 40 50 60 70
Chamber X Aperature (octagon)
Ch
amb
er Y
Ap
erat
ure
(o
ctag
on
)
• Plot Frame Represents Chamber Walls
• B1L & B1R SR Rays
PEP-II Vacuum p19
LER SR Through Q45L HER BellowsLER SR Through Q45L HER Bellows
LER SR Thru Bellows Fingers(0.5 mrad horizontal & 1.0 mrad vertical mis-steer)
-52
-32
-12
8
28
48
-56 -36 -16 4 24 44 64 84 104
Chamber X Aperature (octagon)
Ch
amb
er Y
Ap
erat
ure
(o
ctag
on
)
• Plot Frame Represents Chamber Walls
• All B1L & B1R Rays
PEP-II Vacuum p20
LER SR Through Q5LLER SR Through Q5LLER SR Thru Q5L OBF
(0.5 mrad horizontal & 1.0 mrad vertical mis-steer)
-40
-30
-20
-10
0
10
20
30
40
-72 -22 28 78 128
Chamber X Aperature (rectangular)
Ch
amb
er Y
Ap
erat
ure
(re
ctan
gu
lar)
• Plot Frame Represents Chamber Walls
• All B1L & B1R Rays
PEP-II Vacuum p21
Q5L HER ChamberQ5L HER Chamber
Chamber analyzedChamber analyzed 0 W of LER SR
2560 W of HER SR (B3, B2, BLF)
269 W/m HOM (517 W)
TTmaxmax = = 36 C36 C
max = 13 KSI (combined thermal and mechanical stress).
Re-analyze with 1 kW/m Re-analyze with 1 kW/m HOM, 10% reflected power HOM, 10% reflected power and displacement loads and displacement loads from installation and from installation and manufacturing tolerances.manufacturing tolerances.
PEP-II Vacuum p22
Q4L HER ChamberQ4L HER Chamber
Chamber analyzedChamber analyzed 0 W of LER SR 591 W of HER SR (B3, B2,
BLF) 269 W/m HOM (430 W)
TTmaxmax = 2 = 25 C5 C max = 3.7 ksi (combined
thermal and mechanical stress).
Re-analyze in 3D with Re-analyze in 3D with 1kW/m HOM, 10% 1kW/m HOM, 10% reflected power and reflected power and displacement loads displacement loads from installation and from installation and manufacturing manufacturing tolerances.tolerances.
PEP-II Vacuum p23
Thermal and Mechanical Loading
•Temperature, thermal induced deformation and stress:Q4R Q5R
HOM = 268 w/m HOM = 1 kw/m HOM = 268 w/m HOM = 1 kw/m
Max. Temperature (C ) 10 43 5 20
Max. x deformation (inch) 0.002(out) 0.007(out) 0.008(out) 0.010(out)
Max. y deformation (inch) 0.006(in) 0.005(in) 0.023(in) 0.02(in)
Overall z deformation (inch) 0.020 0.086 0.013 0.05
Max. effective stress (psi) 5520 5540 8916 9400
Q4R Q5R
vacuum
HOM + I2R HOM + I2R
Max. y deformMax. y deform
vacuum
Max. x deformMax. x deform
*On may conclude that overall chamber deformation and stress are vacuum force dominated.
PEP-II Vacuum p24
Beam Position MonitorsBeam Position Monitors
2 Sets of 4 PEP LER Arc Type, Bolt-in BPM’s2 Sets of 4 PEP LER Arc Type, Bolt-in BPM’s
No Additional Sets are Being AddedNo Additional Sets are Being Added
Located Immediately Outboard of Q4 and Q5 Located Immediately Outboard of Q4 and Q5 MagnetsMagnets
Chamber Geometry to Optimize BPM Signal-to-Chamber Geometry to Optimize BPM Signal-to-Noise RatioNoise Ratio
Supporting Chamber at BPM location to the Supporting Chamber at BPM location to the MagnetMagnet
Bellows allows locking Q5 BPM’s in ZBellows allows locking Q5 BPM’s in Z Increases accuracy and stability
PEP-II Vacuum p25
Beam Position Monitor (BPM)
Q5L looking downbeam
Q4R looking downbeam
e-e-
PEP-II Vacuum p26
Old Design
Q4RQ5R
Q2R
Q4R s1Q5R s1
Supports
e -
Q4RQ5R
4” bellow
Q2R
Q4R s1Q5R s1
Q5R s2
BPM
New Design
BPM
PEP-II Vacuum p27
Support Degrees of FreedomSupport Degrees of Freedom
New Design: 8 free DOF x y z pitch yaw roll
ux uy uz rotx roty rotz
Q2L/Q4L HER x x x x x x
Q4L/Bellows HER x x x
Bellows/Q5L HER x x x
Q5L/Frangible Link HER x x x x
Old Design: 3 free DOF x y z pitch yaw roll
ux uy uz rotx roty rotz
Q2/Q4 HER x x x x x x
Q4/Q5 HER x x x x x
Q5L/Frangible Link HER x x x x
"x" designates a fixed constraint
PEP-II Vacuum p28
SupportsSupports
Addition of Bellows Increases Degrees of Addition of Bellows Increases Degrees of FreedomFreedom
Fix Q5 HER Chambers in X, Y & Z at BPMFix Q5 HER Chambers in X, Y & Z at BPM
Isolate Any Thermal Induced Loads in Q5Isolate Any Thermal Induced Loads in Q5
Reduce Any Thermal Induced Loads in Q4Reduce Any Thermal Induced Loads in Q4
PEP-II Vacuum p29
Q4/Q5 Bellows ModuleQ4/Q5 Bellows Module
Q4 side, 10” Q4 side, 10” flangeflange
Q5 side 12” Q5 side 12” flangeflange
GlidCop GlidCop StubStub
Inconel Inconel Spring Spring FingerFinger
GlidCop RF GlidCop RF Shield Shield FingerFingerWelded Welded
BellowsBellows
Cooling – not Cooling – not shownshown
Absorbing Absorbing TileTile
HER arc bellows concept + absorbing tile in bellows cavity.
Nadine to discuss in detail.
PEP-II Vacuum p30
Q5 HER NEG Anti-chamber ScreenQ5 HER NEG Anti-chamber Screen
New Screen DesignNew Screen Design 3 mm diameter holes
through 6 mm thick wall on a 4 mm center-to-center square pattern
Isolate NEG Wafers from HOM Power Allowing Net Pump versus Net Outgassing
Effective Pumping 695 L/s
PEP-II Vacuum p31
Basic Chamber DesignBasic Chamber Design(Q5L HER Shown)(Q5L HER Shown)
Machined, WeldedAluminum Clamshells
PEP LER Arc Type BPM’s
NEG Assembly with Heater Rod(Q5R and Q5L HER Only)
Variable Wall Thickness to BalanceStrength, Magnet Clearance andBeam Clearance
Explosion BondedAl to SST Flanges
Machined PumpScreen
PEP-II Vacuum p32
StatusStatus All Chambers through Preliminary Design ReviewAll Chambers through Preliminary Design Review
All Driving Requirements Have Been IdentifiedAll Driving Requirements Have Been Identified
Preparing Drawings for Long Lead ItemsPreparing Drawings for Long Lead Items
Preliminary Machined Half Estimates ReceivedPreliminary Machined Half Estimates Received
Completing Final Analysis to Support Final Completing Final Analysis to Support Final Design ReviewDesign Review
PEP-II Vacuum p33
Milestone ScheduleMilestone Schedule
Final Design Review – 1/05
Order Long Lead Items – 1/05
Complete Piece Part Drawings - 3/05
Procurements - 3/05
Receive Long Lead Items – 4/05
Receive components, inspection - 6/05
Weld/assemble, Clean and Bake - 7/05
Chambers Ready for Installation - 9/05
End of PresentationEnd of Presentation
PEP-II Vacuum p35
Q5L BPM SectionQ5L BPM Section(looking toward IP)(looking toward IP)
PEP-II Vacuum p36
Q4/5L Clear Luminosity RayQ4/5L Clear Luminosity Ray
Q4L MagnetQ5L Magnet
CorrectorMagnet
Limiting Aperture is Frangible Link-Green Line Represents Clear Aperture-Green Line Clears Q5L & Q4L
PEP-II Vacuum p37
Installation and ServicingInstallation and Servicing
Final alignment in tunnel vacuum chamber Final alignment in tunnel vacuum chamber tolerances are:tolerances are:
Local alignment (4 chambers TBD) X- and Y-tolerance = ± 125 m (.005"). Z-tolerance = ± 1.5 mm (.098"). Pitch and Yaw = ± 1.0 mrad (.06°).
Global alignment X- and Y-tolerance = ± 250 m (.009").
Q4 to Q5 chamber X or Y offset across Bellows Q4 to Q5 chamber X or Y offset across Bellows Module < 0.05".Module < 0.05".
Absolute accuracy of chamber manufacturing Absolute accuracy of chamber manufacturing tolerancestolerances
± 2 mm full width in X (TBD) ± 2 mm full height in Y (TBD)
PEP-II Vacuum p38
Q4 & Q5 Vacuum Chamber RequirementsQ4 & Q5 Vacuum Chamber Requirements Improve alignment and thermal motion of Improve alignment and thermal motion of
chambers. chambers. Maintain gap between chamber and magnet
2 mm minimum between chamber and pole tip, 3 mm minimum between chamber and coil.
Reduce thermal gradient in chambers Change material to Al with water cooling.
Add bellows Reduces reaction forces on chamber supports/raft from
thermal distortion. Reduces reaction forces on chamber supports/raft from
current design due to manufacturing tolerances (pitch, yaw). Addition of a flex flange would further reduce load on the raft
supports, but space constraints make a new design difficult.
Minimize changes to the raft for support Minimize changes to the raft for support modifications.modifications.
Material Properties
Material Aluminum 6061 T6 Stainless Steel (316L)
Young’s Modules
Poisson Ratio
Thermal Expansion
Conductivity
Yield Stress
Tensile Stress
psi6106.10
33.0
Co/1103.24 6
Ccm
wo
56.1
)6(40 Tksi )4(21 Tksi
)6(45 Tksi )4(35 Tksi
psi6100.28
29.0
Co/1108.17 6
Ccm
wo
163.0
ksi42
ksi81
PEP-II Vacuum p40
BPM’sBPM’s Beam Position Monitors (BPM’s)Beam Position Monitors (BPM’s)
Use spare PEP-II BPMs for Al chambers
One set at the outboard end of Q4 and one set at the outboard end of Q5.
Support the BPM set in x and y. Hold in z only if it doesn’t compromise other requirements.
BPM’s are centered on the beam in the x-direction,
Q5L chamber has a BPM center to BPM center x-direction spacing of 1.875” (R. Johnson, S. Smith (2004).
Q5R & Q4 chambers has a BPM center to BPM center x-direction spacing is TBD.
Place BPM’s on flat surfaces. Avoid transitions.
Keep the BPM’s as far away from any holes and masks (at least 4
to 6”). Buttons recessed .012” +/- .009”
PEP-II Vacuum p41
BPM (cont.)BPM (cont.) Support BPM to Quad magnet
No calibration required – QMS/BBA
BPM electrical centerline positional requirements with respect to quad magnetic centerline:
X- and Y- position absolute offset: ± 0.040".
Z-position absolute accuracy: ± 0.060".
Stability X- and Y- long-term stability (precision): ± 0.001".
3 hour time span - motion due to beam current, diurnal temperature, cooling water temperature, beam off/on hysterisis. Does NOT include drift of electronics.
Z long-term stability (precision): ± 0.010".
X- and Y- short-term stability (precision): ± 0.0005". 1 minute time span - motion due to mechanical vibration of chamber with
respect to quad magnet (not of magnet itself). Does NOT include jitter of electronics.
Z short-term stability (precision): ± 0.005"
PEP-II Vacuum p42
PumpingPumping
PumpingPumping Improve average pressure in the chamber (1 e-9 Torr).
Keep NEG in Q5 HER and maximize pumping conductance within screen dimensions.
Improve the screen to reduce broadband impedance and TE leakage into the pump. New Q5 HER screen dimensions: 3 mm (.118”) diameter holes thru 6 mm thick wall, 4 mm x 4 mm square center-to-center pattern.
Add noble diode ion pump at the outboard end of Q5R (TBD).
Add hot filament gauges, new RGA (TBD).
PEP-II Vacuum p43
Fabrication ToleranceFabrication Tolerance
Chamber length tolerance = ± 0.04"Chamber length tolerance = ± 0.04"
Roll/Twist of chambersRoll/Twist of chambers Max allowable twist flange to flange is 3 mrads. This
corresponds to a 0.020" step between Q4 & Q5 chambers.
Pins in bellows will allow for a 3 mrad of roll offset between flange pairs.
Chambers allow for 3 mrad of twist for manufacturing tolerances without applying an excessive load to the supports.
PEP-II Vacuum p44
SupportsSupports
Q4 inboard flanges supported in x, yy, z by the Q2 chamber Q4 inboard flanges supported in x, yy, z by the Q2 chamber support.support.
Q4 outboard flange supported in xx, y to the raft or magnet? Q4 outboard flange supported in xx, y to the raft or magnet? BPM precision will not be as stable as ones held rigidly. BPM precision will not be as stable as ones held rigidly.
Q5 inboard flange support in xx, y to the raft or magnet; or Q5 inboard flange support in xx, y to the raft or magnet; or supported in xx, y, z.supported in xx, y, z.
Q5 outboard flange support in xx, y, z to the raft or magnet; Q5 outboard flange support in xx, y, z to the raft or magnet; or supported in xx, y. If held rigidly here than BPM stability or supported in xx, y. If held rigidly here than BPM stability is improved. Do we need to improve how the BPM is held is improved. Do we need to improve how the BPM is held here? Should we support to the magnet or to the raft or to here? Should we support to the magnet or to the raft or to the concrete pier?the concrete pier?
Supports utilize rod ends and are fully adjustable in the Supports utilize rod ends and are fully adjustable in the field. UNCfield. UNC
Max X or Y deflection under operational loads = ± xxx"Max X or Y deflection under operational loads = ± xxx" Loading at Base of Support (Technical note, xxxx):Loading at Base of Support (Technical note, xxxx):
PEP-II Vacuum p45
Vacuum PressureVacuum Pressure
Average arc pressure ≤ 3.4 x 10-9 torr (N2 equivalent).Average arc pressure ≤ 3.4 x 10-9 torr (N2 equivalent). Average arc base pressure ≤ 5 x 10-10 torr Average arc base pressure ≤ 5 x 10-10 torr
Peak pressure of any bump in profile = 5 x 10-7 torr (NPeak pressure of any bump in profile = 5 x 10-7 torr (N22 equivalent).equivalent).
Operating parameters:Operating parameters: 9 GeV on 2.2A HEB (CDR, p308) crit = 9.8 keV at 9 GeV beam energy (CDR, p309)
Vacuum Calculation VariablesVacuum Calculation Variables Copper & Aluminum
photo = 2 x 10-6 mol/photon (CDR, p310)
photo = 5 x 10-5 mol/photon (CO, Foerster)
therm = 2 x 10-12 torr-L/cm2-s, scaled with temperature (CDR, p310):
therm = 4.0 x 10-12 @ 35°C (beam off)
therm = 1.04 x 10-11 @ 60°C (beam on)
No detectable gas species above mass 44 - measured by RGA.No detectable gas species above mass 44 - measured by RGA.
PEP-II Vacuum p46
Photodesorption DataPhotodesorption Data
C. Foerster
PEP-II Vacuum p47
PSD (cont.)PSD (cont.)
PEP-II Vacuum p48
Running Parameters/Orbit ErrorRunning Parameters/Orbit Error
Design Running Parameters:Design Running Parameters: Fill time = 6 minutes, minimum, (0 to 3 amps HER or 4.5 amps LER).
Full cycles = 10,000 cycles over 20 years , (0 to 3 amps HER or 4.5 amps LER).
Fill cycles = 200,000 cycles, 80% to 100% current (3 Amps HER or 4.5 amps LER), over 20 years.
Max axial beam orbit distortion/steering error (CDR, p 304)Max axial beam orbit distortion/steering error (CDR, p 304) ± 7 mm in X.
± 3 mm in Y.
Max angle beam orbit distortion/steering error (S. Ecklund). Max angle beam orbit distortion/steering error (S. Ecklund). ± 0.5 mrad in X.
± 1 mrad in Y.
Design using a safety factor of 2 for the bellows and elsewhere when possible.
PEP-II Vacuum p49
Heat LoadingHeat Loading
Synchrotron radiation (SR) power Synchrotron radiation (SR) power Chamber ends, SS flange pairs and bellows stubs must be
shadowed by a nominal and mis-steer SR strike.
The RF Seal fingers and Bellows Module shield fingers need to be shadowed from a nominal SR strike and a mis-steer strike with a safety factor of 2.
Secondary back-scatter from SR. Secondary back-scatter from SR. Assume 10% of SR power is scattered onto chamber walls.
In HER arc dipole magnet, 11.6 % of SR is back-scattered off main strike surface. Outside of the field 12.2 % is back-scattered (FLUKA calculations summary by Al Lisin).
PEP-II Vacuum p50
Goal of the ReviewGoal of the Review
Approval of chamber design specification.Approval of chamber design specification.
Approval of chamber design concept and material Approval of chamber design concept and material selection.selection.
Proceed to final design, final design review and Proceed to final design, final design review and detail drawings.detail drawings.
Approval to procure long lead items.Approval to procure long lead items. GlidCop
Transition material
Bellows
Tiles
PEP-II Vacuum p51
Vacuum ProcessingVacuum Processing
In-situ bakeoutIn-situ bakeout There are no provisions being made for an in-situ bakeout. If one is
necessary a hot water system could be implemented and the chambers will survive a bakeout cycle.
Min chamber temperature during in situ bakeout = 95°C.
Max chamber temperature during in situ bakeout = 100°C.
Chamber lab bake-out temperature 150°C.Chamber lab bake-out temperature 150°C.
Glow discharge or TiN coat aluminum chambers to be Glow discharge or TiN coat aluminum chambers to be determined.determined.
Chambers will be scanned for residual gases using a RGA Chambers will be scanned for residual gases using a RGA Mass Spectrometer. When scanning for mass 1 to mass Mass Spectrometer. When scanning for mass 1 to mass 100 at 150100 at 150C, peaks above mass 44 shall be less than 5 x 1-C, peaks above mass 44 shall be less than 5 x 1-12 Torr, and the sum of all peaks above mass 44 shall be 12 Torr, and the sum of all peaks above mass 44 shall be less than 1 x 10-11 Torr.less than 1 x 10-11 Torr.
Material Properties
Material Aluminum 6061 T6 Stainless Steel (316L)
Young’s Modules
Poisson Ratio
Thermal Expansion
Conductivity
Yield Stress
Tensile Stress
psi6106.10
33.0
Co/1103.24 6
Ccm
wo
56.1
)6(40 Tksi )4(21 Tksi
)6(45 Tksi )4(35 Tksi
psi6100.28
29.0
Co/1108.17 6
Ccm
wo
163.0
ksi42
ksi81
PEP-II Vacuum p53
Water Channels
0.256” square with 0.157” diameter bore cooling channels.
2”
Q4R Q5R
2 x 1/16” x 0.25” Skip weld
PEP-II Vacuum p54
Transient Analysis due to Beam Missteering
e-
Temperature contours at t=1 second
SR 0.7 mrad horizontally mis-steered
SR 1 mrad vertically mis-steered
Power density: 14 W/mm (B1(L) + B1(R))Beam height: 0.6mm
PEP-II Vacuum p55
Transient Analysis due to Beam Missteering
•Note that temperature rise within missteering area due to HOM + I2R
• 16 C (HOM + I2R power density 1Kw/m is used)
•Place few thermocouples, one of the thermocouple will experience temperature rise during beam missteering
•14 C (if max trip stress is 25 ksi, max. temperature rise 97 C ) •30 C (if max trip stress is 30 ksi, max. temperature rise 116 C)
•Assume water temperature
30 C
•Due to uncertainty of HOM power density, Nominal trip temperature is set to be
46 C (30 + 16) (=115 F)
•Maximum trip temperature
60 C (30 + 30) (=140 F)
is used.
PEP-II Vacuum p56
Reaction Forces due to Support ScenarioQ4R + Q5R
Forces (lb) Moments (lb-in)
X Y Z X Y Z
Caused by
1 mrad yaw
1 mrad pitch
Z constraints
1 mrad pitch
1 mrad yaw
1 mrad twist
Q2R 256 153 0 -6488 9503 -1360
Q4R s1 -332 -137 0 0 0 -569
Q5R s1 N/A N/A N/A N/A N/A N/A
Q5R s2 76 70 0 0 0 1930
Net 0 87* 0 -6488 9503 0
*Body force included.
Q2RQ4R S1
Q5R S2
Q4R
Q5R
Q4R + 4” Bellow + Q5R
Reaction Forces (lb) Reaction Moments (lb-in)
X Y Z X Y Z
Caused by
1 mrad yaw
1 mrad pitch
Z constraints
1 mrad pitch
1 mrad yaw
1 mrad twist
Q2R 91 -89 0 5113 5911 1360
Q4R s1 -91 60 0 0 0 -1360
Q5R s1 0 18 0 0 0 3070
Q5R s2 0 38 0 0 0 -3070
Net 0 87* 0 5113 5911 0Q2R
Q4R S1
Q5R S1
Q5R S2
Q4R
Q5R
Bellow
e-
z
x
y