ILC Accelerator Baseline Design (TDR-2): SCRF Cavity and Cryomodule

Akira Yamamoto KEK/ILC-GDE on behalf of

GDE Project Managers and SCRF TA Collaborators

Report for Project Advisory Committee (PAC) Review, To be held at KEK, 13th December, 2012

ILC Accelerator Baseline Design (TDR-2):

SCRF Cavity and Cryomodule

A. Yamamoto, 2012.12.13 ILC-PAC SCRF 1

A. Yamamoto, ASC-2012 2Advances in SCRF for ILC

• We (GDE-PMs) would thank the ILC-GDE, SCRF collaboration with:

– DESY, INFN, CEA-Saclay, LAL-Orsay, CI, CERN, and Industry in Europe,

– FNAL, J-LAB, Cornell, SLAC, ANL, LANL, BNL, TRIUMF, and Industry in Americas,

– KEK, Kyoto, IUAC, RRCAT, BARC, TTIF, VECC, IHEP, PKU, PAL, KNU, PNU, and Industry in Asia

for their worldwide cooperation in TDR

Acknowledgments

SCRF Reports for PAC

TDR2-Chapter 3• Main Linac Layout

– Common layout– Flat and Mountainous

topologies • by Marc Ross

• SCRF Technology – Cavity and Cryomodule

• by Akira Yamamoto– RF Power System

• by Shigeki Fukuda


Outline

• Introduction– Baseline technologies achieved for TDR

• Cavity and CM Baseline Design for TDR– Cavity

• Production Specification (S-3.2) • Cavity Integration (S-3.3)

– Cryomodule • Cavity string and CM Design Incling Quad. (S-3.4)

– Cryogenic • Cooling Scheme (S-3.5)


Introduction

• Progress to establish baseline technologies for ‘TDR’ – Cavity gradient (S0):

• Worldwide effort: G = 35 MV/m+/- 20%, satisfying <G> ≥ 35 MV/m – Cavity and Cryomodule (CM) integration (S1):

• ‘S1-Global’ verified baseline technologies– Beam acceleration with SCRF CM (S2):

• ‘FLASH’ demonstrated ILC beam current and the pulse-duration • “STF-QB’ demonstrated ILC beam pulse-duration


Global Plan for SCRF R&D

Year 07 2008 2009 2010 2011 2012

Phase TDP-1 TDP-2Cavity Gradient in v. test to reach 35 MV/m Yield 50% Yield 90%Cavity-string to reach 31.5 MV/m, with one-cryomodule

Global effort for string assembly and test(DESY, FNAL, INFN, KEK)

System Test with beamacceleration

FLASH (DESY) , NML/ASTA (FNAL) QB, STF2 (KEK)

Preparation for Industrialization

Production Technology R&D

Communication with industry:

1st Visit Vendors (2009), Organize Workshop (2010) 2nd visit and communication, Organize 2nd workshop (2011)3rd communication and study contracted with selected vendors (2011-2012)

A. Yamamoto, ASC-2012 6Advances in SCRF for ILC

We are here

Configuration: RDR to TDR

7A. Yamamoto, ASC-2012 Advances in SCRF for ILC

RDR-2007 TDR-2012

Cost containment Motivation:

• Single accelerator tunnel• Smaller damping ring• e+ target at high-energy end, • Cavity G. 31.5 MV/m +/- 20 %, • HLRF and tunnel layout:

– Klystron-Cluster on surface (KCS), or

– Distributed Klystron in tunnel (DKS)

Flat-land or Mountainous Tunnel Design

5 m

Cavity Gradient: Production Yield, Yearly Progress

9

Year 2010 - 2012 1st cycle 2nd cycle

G≥ 28 MV/m 67 (+/-10) % 94 (+/-6) %

G≥ 35 MV/m 38 (+/-11) % 75 (+/-11) %

<G> above 28 MV/m 35.1 MV/m 37.1 MV/m

Cavity Gradient: Production Yield Progress since 2006


2nd pass statistics for 2010 ~ 2012 period: Production yield: 94 % at > 28 MV/m, Average gradient: 37.1 MV/m

- Integrated statistics since 2006 in 2nd pass yield- Max. gradient achieved: > 45 MV/m

Gradient Spread of +/- 20%

• Average gradient of 35 MV/m– with the spread of 28 ~ 42 MV/m (+/- 20%)– Cavity gradient: higher spread (+ 20%) absorb the lower

spread (- 20 %), • Cost-effective production by increasing yield

– gaining > 15% (19 %) higher production-yield, – corresponding to ~ 15% saving cavity production cost.

• ( investment cost, unchanged) • 75 % at ≥ 35 MV/m to 94 % at ≥ 28 MV/m

• Necessary trade-off with additional RF power – RF power addition required, but it less expensive.


Cavity String and CM system integration: demonstrated by S1-Global

A. Yamamoto, LINAC12, 120913-b Status of ILC

DESY, FNAL, Jan., 2010

INFNand FNALFeb. 2010

FNAL & INFN, July, 2010

DESY, May, 2010March, 2010 June, 2010 ~

DESY, Sept. 2010

12

13

Blade Tuner (INFN/FNAL) Saclay Tuner (DESY)

Slide-Jack Tuner (KEK)

TTF-III Coupler (DESY/FNAL/SLAC) STF-II Coupler (KEK)

TESLA Cavity (DESY/FNAL)Tesla-like Cavity (KEK)

Cavities, Tuners, Couplers in S1-G Cryomodule

110809, A. Yamamoto ILC-SCRF-Global-Effort

TESLA (DESY) and TESLA-Like (KEK) Cavity

121005 KEK-LC-STF meeting 14

Variety of Cavity and Tuner Assembly in S1-Global


Blade Tuner (originated by INFN)Slide-jack tuner at KEK EXFEL tuner

S1-Global Progress ReportAvailable as an attached manuscript


Cavities Performance:

C1 C2 C3 C4 A1 A2 A3 A4Before cryomodule installation

after cryomodule installation

7 cavities combined operation

31.5 MV/m

Average 30.0MV/m

Average 27.7MV/m

Average 26.0MV/m

GradientE. Kako, H. Hayano

Stability in 6300 sec.LLRF stability study with 7 cavities operation at 25MV/m

Field Waveform of each cavity

- Vector-sum stability: 24.995MV/m ~ 24.988MV/m (~0.03%)- Amplitude stability in pulse flat-top: < 60ppm=0.006%rms- Phase stability in pulse flat-top: < 0.0017 degree.rms

vector-sum gradient

amplitude stability in pulse flat-top

phase stability in pulse flat-top

7-cavity operation by digital LLRF

A. Yamamoto, ASC-2012 Advances in SCRF for ILC 18

Designs Demonstrated in S1-Global and the Baseline Technology selected for TDR

Element Varieties Notes Meet ILC req.

Baseline for TDR

Resonator Tesla/EXFELTesla-like

- Cell-taper: 13 deg., lower rigidity- Cell-taper: 10 deg., higher rigidity

YesYes

Tesla/EXFEL:Less expensive

Input Coupler TTF-IIIKEK-STF

- Bellows at cold-outer-pipe - Solid-cold-pipe, flex. inn-antenna

YesYes

TTTF-II; less-expensive

Tuner Scissor-EXFELBladeSlide-jack

- Require longer BP length- Lower-rigidity- Higher-rigidity

Out of scopeYesYes

Blade; less-expensive

He-tank EXFELBladeSlide-jack

- Simplest structure- Bellows at center- Motor placed outside

Out of scopeYesYes

Blade: less expensive

Mag. shield OutsideInside

- Installation during CM ass.- Installation in cavity fabr.

YesYes Inside; simplest

Beam flange Al-gasketHelico-flex

- Well experienced, world-wide- Experienced at KEK

YesNot taken

Al-gasket: well experienced


Plug-compatible Conditions

Plug-compatible interface established

Item Variation TDR Baseline

Cavity shape TESLA / LL TESLA

Length Fixed

Beam pipe flange Fixed

Suspension pitch Fixed

Tuner Blade/Slide-Jack

Blade

Coupler flange (cold end)

40 or 60 40 mm

Coupler pitch Fixed

He –in-line joint Fixed

12/05/14 20KEK-LC-Meeting

Beam Acceleration Parameters required for ILC-TDR

Parameters ValueC.M. Energy 500 GeVPeak luminosity 1.5 x1034 cm-2s-1

Beam Rep. rate 5 HzPulse duration 0.73 msAverage current 5.8 mA (in pulse)

Av. field gradient 31.5 MV/m +/-20%Q0 = 1E10

# 9-cell cavity 16024 (x 1.1)# cryomodule 1,855

# Klystron ~400

A. Yamamoto, ASC-2012 Advances in SCRF for ILC 21

Progress in SCRF System Tests • DESY: FLASH

– SRF-CM string + Beam, • ACC7/PXFEL1 < 32 MV/m >

– 9 mA beam, 2009– 800ms, 4.5mA beam, 2012

• KEK: STF– S1-Global: complete, 2010

• Cavity string : < 26 MV/m> – Quantum Beam : 1 ms – CM1 + Beam, in 2014

• FNAL: NML/ASTA– CM1 test complete– CM2 operation, in 2013– CM2 + Beam, beyond

2013A. Yamamoto, ASC-2012 22Advances in SCRF for ILC

Summary: SCRF Baselines Demonstrated and/or chosen for TDR

• Cavity gradient – Achieved 35 MV/m +/- 20 %, and < 37.1 MV/m> with

the production yield of 94%• Cavity and CM integration

– Demonstrated SCRF technologies available for TDR• Coupler : TTF-III• Tuner: Blade tuner• Magnetic shield : placed inside LHe tank

• Beam acceleration– Demonstrated ILC beam parameters

• Beam (RF) pulse duration: 1 ms• Beam current: 9 mA


Outline

• Introduction– Baseline technologies achieved for TDR

• Cavity and CM Baseline Design for TDR– Cavity

• Production Specification (S-3.2) • Cavity Integration (S-3.3)


– Cryogenic • Cooling Scheme (S-3.5)


Cavity Design Parameters


YS-delivered: > 50 MPa -annealed: > 39 MPaP-design: 0.2 Mpa -test:: 0.3 MPa

Cavity/Cryomodule Fabrication

A. Yamamoto 11/13/2012 26

He Tank

Material/Sub-component

Cavity Fabrication

Surface Process

LHe-Tank Assembly

Vertical Test =Cavity RF Test

CryomoduleAssembly and RF Test

Cavity Fabrication/Test Process Flow


< 30 mm

Local repair, if it be economical

2nd pass, if G < 35 MV/m(as of today) 60 % go to 2nd pass

Cavity Gradient: Production Yield, Yearly Progress

28

Year 2010 - 2012 1st cycle 2nd cycle

G≥ 28 MV/m 67 (+/-10) % 94 (+/-6) %

G≥ 35 MV/m 38 (+/-11) % 75 (+/-11) %

<G> above 28 MV/m 35.1 MV/m 37.1 MV/m

Fabrication and Surface Treatment Process

29

Parameters to be further optimized

micron

Subjects for Further Study• Vertical Test with LHe tank

– Production economical, but defects may not be localized with having LHe tank,

• Local repairs – More experiences needed to understand the cost-saving,– New definition for production yield including repair,

• Mitigation of field emission and radiation – Understand sources and mitigation technology

• Establish quantitative evaluation technology


Cavity Integration


• 9-cell resonator• Input-coupler

– TTF-III coupler • Frequency tuners

– Blade tuner• He tank• Magnetic shield

– Inside He tank

Input Coupler Design Specification


Design needs to be ready for upgrade

Coupler Fabrication and Process

• Coupler fabrication– At industry

• Coupler Process– At industry or lab.

• String Assembly with CM– At lab.


Baseline: TTF-III Coupler• Reasons

– Much experience at FLASH (DESY), ASTA (Fermilab)– Used in EXFEL– Demonstrating the ILC technical requirement – Less expensive

• Subjects for further study beyond TDR– Seeking for further optimum design with fixed (no-bellows) cold-

end outer-pipe, referring the KEK coupler design,– Simplifying the assembly process, with keeping less expensive

design


TTF-III Coupler: various support jigs are required.

coupler assembly

KEK STF Coupler:self standing

Tuner Design Specification


Baseline: Blade Tuner

• Reasons– Demonstrating the ILC technical requirements (S1-

Global, ASTA) – Less expensive

• Subjects for further study beyond TDR– Judgment for MTBF/reliablity and maintain-ability of –

pulse-motors and piezo-motors– Seek for a further optimum design to allow

accessibility/maintain-ability for the motors,


He Tank Design with Blade Tuner


Bellows at Center


LHe Tank Comparison Lhe tank for Slide-jack Tuner

Lhe tank for Blade Tuner

Baseline: LHe tank w/ Blade Tuner

• Reasons– Simpler and less expensive than the design with

slide-jack tuner,

• Subjects for further study beyond TDR– Further simple design for cost-reduction to be

comparable with the EXFEL LHe-tank


cylindrical shield inside jacket

Pill-box end-cell shield, outside jacket(may be required for Tesla-Cavity design)

Conical shield inside endplate

Design concept: inside shield + cylindrical end shield outside

Magnetic Shield Inside LHe Tank

For 2 KEK Cavities For 2 FNAL Cavities

16 Components per ca (shield outside 4 Components per Cavity (shield inside)

Comparison of Magnetic Shield

Baseline: Magnetic-Shield Inside• Reasons

– Simplest and best shielding effect with the minimum connection-interfaces and holes

– Efficient installation work during cavity integration, and minimum work during cavity string assembly

• Subjects for further study beyond TDR– Industrialization of magnetic shield cylinder – Conical shield installation for TESLA type cavity

having spatial conflict at the end-cell contact to the conical flange


Plug-compatible Conditions

Plug-compatible interface established

Item Varieties BaselineCavity shape TESLA / LL TESLA

Length Fixed

Beam pipe flange Fixed

Suspension pitch Fixed

Tuner Blade/Slide-Jack

Blade

Coupler flange (cold end)

40 or 60 40 mm

Coupler pitch Fixed

He –in-line joint Fixed


Outline• Introduction

– Baseline technologies achieved for TDR• Cavity and CM Baseline Design for TDR

– Cavity • Production Specification (S-3.2) • Cavity Integration (S-3.3)


– Cryogenic system • Cooling Scheme (S-3.5)


Cavity/Cryomodule Fabrication

He Tank

A. Yamamoto 11/13/2012 46

Material/Sub-component

Cavity Fabrication

Surface Process

LHe-Tank Assembly

Vertical Test =Cavity RF Test

CryomoduleAssembly and RF Test

CM Assembly


12.652 m (slot length)

cavities (8) SC quad packageType-B moduleType-A has 9 cavities and no quadrupole

Cryomodule Design

Cryomodule Gradient Spread and Degradation Observed at DESY and KEK, as of Nov. 2010

• FLASH: – 3 PXFEL cryomodules

• ILC R&D:– S1-Global cryomodule– CM1 (S1-Local @ Fermilab)

• Current status: – 12/40 degraded with ~ 20 %

A. Yamamoto -110928 TDR ACC & SCRF Guidline 49

1 - AC129 2 - AC123 3 - AC125 4 - Z143 5 - Z103 6 - Z93 7 - Z100 8 - AC1130

510

15

202530

35

40

FLASH 30MV/m XFEL goal

13.07.2009

EA

CC [M

V/m

]

cavity

Cavity tests: Vertical ( CW ) Horizontal (10Hz) CMTB M8 (10Hz) CMTB (10Hz)

very

long

CW

cond

ition

ing

Cavities gradient limits

1 - Z141 2 - AC150 3 - Z133 4 - Z139 5 - AC122 6 - AC121 7 - AC128 8 - AC1150

5

10

15

20

25

30

35


XFEL goal

04.05.2010

EA

CC [M

V/m

]

cavity

Cavity tests: Vertical ( CW ) Horizontal(10Hz) CMTB (10Hz)

MP

1 - Z135 2 - AC124 3 - Z88 4 - Z134 5 - Z101 6 - AC127 7 - Z140 8 - Z970

5

10

15

20

25

30

35


XFEL goal

13.09.2010E

AC

C [M

V/m

]cavity

Cavity tests: Vertical ( CW ) Horizontal(10Hz) CMTB (10Hz)

MP

FE

FE

PXFEL-1 PXFEL-2 PFEL-3

S1-Global

D. Kostin & E. Kako

Conduction-Cooled Split-able Quadruple


Advantages;- Q-magnet may be assembled separately,- Keep “best clean” during cavity string assembly- No additional cryostat and cryogenics- Highly accurate alignment without LHe vessel

Heat Loads per CM

51

Cooling Scheme of a Cryo-string


ML Heat Load and Cryogenics Plant Size

53

Cryogenics System Layoutto be explained by M. Ross


Adaption to High Pressure Code • Basic design

– High pressure code to be applied • ASME (US), TUV (DE/EU), High Pressure Code (JP) basically

consistent, but some difference in detail

• Fundamental parameters (for example)• Design Pressure: 2 bar (difference) • Test pressure : 1.5 x 2 = 3 bar (in case of water)• 1.25 x 2 = 2.5 bar (in case of gas) • Maximum stress: 2/3 of 0.2 % yield strength at RT

– Meaning at weakest temperature

• Required test and plan: – Pressure test, leak-tight test – Documentation: fabrication/welding plan and sample test.


Baseline: TESLA Type-IV Cryomodule

• Reasons– Well experienced and mass production in

progress, and very similar to EXFEL CM.– Assembly procedure well understood

• Subjects for further study beyond TDR– 5K radiation-shield (bottom part) removable for

cost-effective production and assembly – Gas-flow direction better to be reversed for more

efficient 5K thermal intercepts – Mitigation of cavity gradient degradation during

Cryomodule assembly.


Two shield model One shield model

5K-shield partially removableFurther Study beyond TDR:


- 5K-shield at bottom removable- Simplify the CM assembly work - Better accessibility

KEK-LC-Meeting

SCRF Procurement/Manufacturing Model

Regional hub-laboratories responsible to regional procurements to be open for any world-wide industry participation

Regional Hub-Lab:E, & …

Regional Hub-Lab:

A

Regional Hub-Lab:

B

Regional Hub-Lab:

D

World-wideIndustry responsible to

‘Build-to-Print’ manufacturing

ILC Host-Lab

Regional Hub-Lab:C: responsible to Hosting System

Test and Gradient Performance

Technical Coordinationfor Lab-Consortium

: Technical coordination link : Procurement link

12/05/14 58

Industrial Participation to ILC Cavity Production

• Progress in EXFEL (as of Oct. 2012) (courtesy by D. Reschke: the 2nd EP at DESY)

– RI: 4 reference cavities with Eacc > 28 MV/m, (~ 39 MV/m max.)– Zanon: 3 reference cavities with Eacc > 30 MV/m ( ~ 35 MV/m max.)

12/05/14 KEK-LC-Meeting 59

year # 9-cell cavitiesqualified

# of Labs reaching 35 MV/m processing

# of Industrial manufacturers reaching 35 MV/m fabrication

2006 10 1 DESY

2 ACCEL, ZANON

2011 41 4 DESY, JLAB, FNAL, KEK

4 RI, ZANON, AES, MHI,

2012 (45) 5 DESY, JLAB, FNAL, KEK,

Cornelland others joining soon

5 RI, ZANON, AES, MHI, Hitachi

and others joining soon

KEK-LC-Meeting

The 3rd Cycle Communication with CompaniesFurther studies with contracts in 2011-2012

Date Company Place Technical sbject1 2/8, 2011 Hitachi Tokyo (JP) Cavity/Cryomodule

2 2/8 Toshiba Yokohana (JP) Cavity/Cryomodule, SCM

3 2/9 MHI Kobe (JP) Cavity / Cryomodule

4 2/9 Tokyo Denkai Tokyo (JP) Material (Nb) 5 2/18 OTIC NingXia (CN) Material (Nb, NbTi, Ti)

6 (3/3), 9/14 Zanon Schio (IT) Cavity/Cryomodule

7 3/4, RI Koeln (DE) Cavity

8 (3/14), 4/8 AES Medford, NY (US) Cavity

9 (3/15), 4/7 Niowave Lansing, MI (US) Cavity/Cryomodule

10 4/6 PAVAC Vancouver (CA) Cavity

11 4/25 ATI Wah-Chang Albany, OR (US) Material (Nb, Nb-Ti, Ti)12 4/27 Plansee Ruette (AS) Material (Nb, Nb-Ti, Ti)13 5/24 SDMS Sr. Romans (FR) Cavity14 7/6 Heraeus Hanau (DE) Material (Nb, Nb-Ti, Ti)15 10/18 Babcock-Noell Wurzburg (DE) CM assembly study16 11/11 SST Maisach (DE) Electron Beam Welder

6012/05/14

KEK-LC-Meeting 61

Mass-Production Studiesin contracts

Company Mass production model

Contract funded/hosted by

Cavity RI in progress 100% (50%) DESY

AES 20 % DOE/Fermilab

MHI 20, 50, 100% KEK

Quadrupole Toshiba 100 % KEK

CM and assembly Hitachi 20, 50, 100% KEK

AES 25% DOE/Fermilab

CM assembly BN in progress 100, 33 % CERN

In parallel, EXFEL experience kindly informed by DESY, INFN, CES/Saclay

12/05/14

Industrial study led by CERN/GDE• Study, based on EXFEL CM assembly specifications and Work

Break-down Structure (WBS) • But including ILC specificities (see below)

V. Parma

63

Beam

8 July 2011

12/05/14 KEK-LC-Meeting

Cavity Fabrication and IndustrializationR&D Facility being realized at KEK

Cryomodule Assembly work layout/flow for EXFEL at CEA/Saclay, as a reference


EXFEL Cavity/Cryomodule Test Station as a reference

• If we may have ~ 3 of this test station, the ILC cavity/cryomodule test can be managed.

• We may consider ~ x 3 ( = 20 (or 15) / 2 period / 3 regions ) • Or, it is just enough, if 1/3 cryomodules to be tested in ILC


IT racks

IT racks

16

UV6UV4

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Sicherheitslichtgerät

Hauptverteilung

UV8UV5

UV7

MPS

Subcooler

Valve

box

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Control building

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Mounting area cavities

Vertical cryostats

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Storage areafor modules

MHF-sl,MVS racks

Reserve racksReserve racksReserve racks

MHF-sl racks MHF-sl racks MHF-sl racks

User's racksUser's racks

User's racksLHe tank

RF ar

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Courtesy: H. Weise (DESY)

Production Process/Responsibility Step hosted Industry Industry/

LaboratoryHub-laboratory

ILC Host-laboratory

Regional constraint no yes yes yes

Accelerator - Integration, Commissioning

Accelerator sys. Integ.

SCRF Cryomodule - Perofrmance Test

Cold, gradient test

As partly as hub-lab

Cryomodule/Cavity- Assembly

Coupler, tuner, cav-string/cryomoduleassmbly work


Cryomodule component- Manufacturing

V. vessel, cold-mass ...

9-cell Cavity- Performance Test

Cold, gradient test


9-cell Cavity - Manufacturing

9-cell-cavity assembly, Chem-process, He-Jacketing

Sub-comp/material- Production/Procurement

Nb, Ti, specific comp. …

Procurement


Cryomodule Test: Work Flow


- 1/3 of Cryomodules tested on surface - Additional 5 % tested for initial stage- Totally 38.5 % CMs tested on ground

Tested on surface Directly commissioned in tunnel

Baseline: Cavity/CM Assembly and Test

• Cavity and Cryomodule components– Manufactured by Industry– Couplers need to be conditioned at industry or laboratory

• Cavity-string and CM assembly– Work hosted at Hub-laboratories w/ contracted work by

industry

• Cavity qualification tests– 100% (actually > 110 %) done at laboratories

• Cryomodule qualification tests– 33 + 5 % tests, at hub-laboratories, and others directly

installed in the ML tunnel and commissioned,


Summary • Cavity design and fabrication

– Gradient: 35 MV/m +/- 20%, keeping <35 MV/m> and the production yield of > 90% within the 2nd pass surface process

– Design and fabrication process, referring TESLA/EXFEL experiences, except for ‘tuner’ design based on ‘Blade tuners’,

– Plug-compatible design for cavity integration and the boundary conditions fixed, and further improvement to be enabled under the plug-compatible interface condition,

– Cavity qualification tests• 100 % test • Vertical test w/ He tank is to be experienced by EXFEL

– Coupler, Tuner and LHe tank: Subjects for further study beyond TDR• Cryomodule design, fabrication, assembly, and tests

– Design, fabrication, and assembly process, referring FLASH/EXFEL, – Cryomodule qualification tests

• 33 + 5 % test in test facilitym and other CM directly installed into tunnel,– 5 K shield (bottom radiation shield) removable is a subject to be further

studied beyond TDR, for cost-saving,69

backup


He Tank Design Comparison

EXFEL/FLASH/TESLA LHe tank w/ Saclay/Desy tuner at the axial end

ILC LHe tank design with ‘Blade Tuner’ at the axial center


Note:Re-visiting overall design of tuner and LHe tank may be required

FNAL cavity KEK-type1 cavityat S1-Global

Slide-jack tunerBlade tuner TTF-III coupler

KEK coupler

Tuner

KEK STF Coupler TTF-III Coupler(2) Coupler

75

Legend

Toward coupler sideToward pick-up side coupler side motor side

top

bottom

Driving unit support elements are already installed on the tuner halves.

Preassembled parts

121005 KEK-LC-STF meeting

Plug-compatible Interfaces


Plug-Compatible Interfaces


From the slide by Don

Magnetic shield on FNAL cavities with blade tuner at S1-Global

Magnetic shield inside for KEK cavities

(3) Magnetic shield

no more work during cryomodule assembly

assembly work during cryomodule assembly

Cavity Package

Frequency (“blade”) tuner

High-power coaxial input coupler

A. Yamamoto 11/13/2012 79

Cryomodule Design for TDR-33. Magnetic shield design

– Outer magnetic shield and inner magnetic shield– Comparison of the procedures and the cost of assembly

in cryomodule

DESY cavity outer magnetic shield

FNAL cavity outer magnetic shield

KEK cavity inner magnetic shield (red line)

Main Linac He Inventry


(2) Coupler

TDR Baseline candidate

TTF-III coupler (RDR baseline)

KEK coupler

Design Concept Two cylindrical window, coupling tunable

Two disk window, no outer bellows in cold part but tunable

merit Wide coupling range, low heat load

High power capability window, easy handling of cold part installation

drawback Complex installation jig and procedure required

demonstration FLASH cryomodules, S1-Global, FNAL CM-1(>50 couplers)

STF phase-1, S1-Global KEK cavities (8 couplers)

failure Bolts stuck in disassembly High heat load, breakdown,

Cost

Choice/decision choice, because of well established power transmission with low heat load.

Tuner


Blade tuner Slide-jack tuner

Design Concept Twist mechanism with torsion plates + LV-piezo + motor&gear-inside

Stiff end-plate + stiff slide-jack + HV-piezo + drive-feedthrough&motor-outside

merit fine step with small backlash

Small LFD small piezo stroke, motor maintenability

drawback He-jacket-bend-risk at tuner (Jacket center)

Precise mechanics alignment required, Mechanics heavy

demonstration S1-Global FNAL cavities(27MV/m), FNAL 14 cavities HTS test for CM-2(35MV/m)

STF phase-1 cavities, S1-Global KEK cavities(38MV/m)

failure (need design upgrade )

Motor-gear connection slip, piezo breakdown, drive CuBe screw stuck, motor wire short

mechanical stuck by slide-slope bending(weld-bend)

Cost (cost ratio) Choice/decision choice, because of low

cost

(3) Magnetic shield


Shield outside of cavity jacket

Shield inside of cavity jacket

Design Concept

avoid complex shield installation around tuner region

merit avoid complex shield installation around tuner region

drawback Complex installation required (16 pieces)

demonstration for each tuner candidate

S1-Global FNAL cavities ( 2 cavities )

STF phase-1 cavities, S1-Global KEK cavities (8 cavities )

failure none none

Cost

Choice/decision

choice, because of simple assembly benefit

(4) Flange seal


Al hexagonal Sn (In) coated Helicoflex

Design Concept metal-crash-seal concept stress-back-seal concept

merit Less contamination, HPR washable

Small torque fixing, spring-back force for heat cycle

drawback no reuse Risk of coat-metal powder contamination, contamination in spring housing

demonstration FLASH cavities, S1-Global FNAL,DESY cavities, FNAL CM-1 cavities ( >70 cavities )

STF phase-1 cavities, S1-Global KEK cavities ( 8 cavities )

failure met bad-coating lot

Cost ratio

Choice/decision choice, because of many demonstration results

* Flange aperture should be follow TESLA cavity (base-line) design

HLRF-DKS upgrade option

18 Jan 2012 KEK, SC BTR 86

5 K shield

18 Jan 2012 KEK, SC BTR

• Flow inversion allows removal of bottom 5K shield, but with important design modification– Rearrangement of module cross-section– Rerouting of thermal intercepts

• No time or resources to complete such and effort in TDR, comfortably leave it to the final «optimized» engineering stage– Assume for TDR the XFEL proven concept

• Risk free, huge data provided by XFEL tests– Reversal is «cost neutral»

• [besides design effort, piping is the same]

87

5 K shield

18 Jan 2012 KEK, SC BTR

• Proposal for TDR the 5 K shield remains, however, it can be simplifed– We can allow a decrease in static efficiency

providing options to allow assembly operations or some access from vessel flanges to the string, if desired

– Shields at the module interconnections can be avoided

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ILC Accelerator Baseline Design (TDR-2): SCRF Cavity and Cryomodule

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