superconducting rf cavity/cryomodule development at fermilab (industrialization) c.m. ginsburg...

Superconducting RF Cavity/Cryomodule Development

at Fermilab(Industrialization)

C.M. Ginsburg (FNAL)

Proton Accelerators for Science and Innovation

2nd Annual Meeting

Rutherford Appleton Laboratory, UK

3-5.April 2013

FermilabOverview

SRF activity at FNAL/ANL is in support of Project X, ILC, or other future SRF projects Explicitly includes industrial development, and associated R&D for improved

performance and reliability, and reduced cost Infrastructure availability and personnel development permit the

development of industrial partners for SRF cavities and cryomodules FNAL philosophy: the laboratory does not duplicate activity or compete

with industrial capability Industry can provide most materials and services more quickly at lower cost Exceptions involve substantial infrastructure, e.g., cryogenic systems

Most of the industrialization focus has been for the ILC, so this talk will be weighted toward ILC (electron) technology Most conclusions are broadly applicable to other SRF projects ...Proton accelerators in particular

5.Apr. 2013 Ginsburg (FNAL) 2nd PASI Workshop 2

FermilabOutline

Cavity vendor development Cavity processing vendor development Cavity and cryomodule value engineering Cryomodule assembly

Not yet industrialized in the US; XFEL example will be instructive Existing industrialization workshops (ILC)


FermilabBare cavity sequence

Each inspection, processing and test step is recorded in an electronic traveler

4 Ginsburg - NGLS Review Feb 5-8, 20135.Apr. 2013 4Ginsburg (FNAL) 2nd PASI Workshop

For large projects like XFEL, it may make sense to dress cavities before vertical test

FermilabCavity dressing sequence


FermilabCM assembly sequence (part 1)


Receive dressed cavities at CAF-

MP9

Receive peripheral parts

Assemble dressed Cavities to form a

String in the Cavity String

Assembly Area (Clean Room)

Install String Assembly to Cold Mass in the Cold Mass Assembly Area

Transport the Cold Mass to CAF-ICB

FermilabCM assembly sequence (part 2)


Install the String assembly with the cold mass into the Vacuum vessel in the Vacuum Vessel

Assembly area

Install the Cold Mass back to the Cold Mass Assembly Fixture in

Cold Mass Assembly Area

Align Cavity String to the Cold Mass

Support

Ship Completed Cryomodule to ILCTA-

NML for testing

FermilabILC cavity: international effort

• ILC cavity fabricators– Research Instruments (Germany)– Zanon (Italy)– Advanced Energy Systems (US)– Niowave and Roark (US)– PAVAC (Canada/US)– Mitsubishi Heavy Industries (Japan)– Toshiba (Japan)– Hitachi (Japan)

• ILC cavity processing facilities– DESY– Jefferson Lab– KEK– Fermilab/Argonne joint facility– (Industrial processing facilities: RI, AES, Zanon)

• Results from past 3 years have been collected in worldwide database, as a means to further track progress and provide input to ILC machine design


• Cavity from vendors who have manufactured a cavity that has surpassed 35MV/m in vertical test: – ACCEL or ZANON or (AES SN>=5) or (MHI SN>=12)

• Fine-grain cavity• Use the first successful (= no system problem) test• Standard EP processing: no BCP, no experimental processes• (Ignore test limitation)• Second pass

– if (Eacc(1st successful test)<35 MV/m) then• if (2nd successful test exists) then

– plot 2nd test gradient• else

– plot nothing [assume 2nd test didn’t happen yet]• endif

– else• plot 1st successful test gradient

– endif

“Up-to-second-pass” ILC Production Yield Plot - Method

5.Apr. 2013 9Ginsburg (FNAL) 2nd PASI Workshop

FermilabILC Cavity Performance Benchmark

Ginsburg (FNAL) 2nd PASI Workshop

International cavities from established vendors using established processes2nd pass yield for >35 MV/m for integrated sample is (57 +- 8)% for 2010-2012 alone is (69 +- 13)%

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FermilabGradient Summary

• Good progress worldwide in cavity production, processing, and test• AES has been qualified as an ILC cavity vendor during this activity• Progress is a partnership between industry and laboratories, results are

dependent on both performing well– Scars, pits, stains, dirt and residue introduced at different steps– Early defects are not typically overcome by the standard processing steps

• The typical learning curve at each company requires a ‘few’ cavities– constant vigilance required afterwards to stay there

• Yield statistics to the ILC specification show improvement with time– Utility of XFEL test data for ILC will be limited by XFEL requirements, but huge data set

• Efforts to exceed ILC gradient spec will continue– Field emission prevention at all gradients remains important

• Laboratory processing and test facilities are coming up to speed, recent throughput at Fermilab for instance is very good


Fermilab

Canadian company with new facility in Batavia

1-cells: 6 fine-grain cavities fabricated – Half use “smart-”bells TE1PAV001-3

• First weld together half-cells, then add beamtubes

– Half use dumb-bells – TE1PAV004-006• First weld each half-cell to a beamtube,

then weld together • “smart bell” cavities exhibited

multipacting ~18-22 MV/m possibly due to unusual shape

9-cells: 10 fine-grain cavities were ordered; order later changed to 650 MHz

New Vendor Development: PAVAC

TE1PAV001

12Ginsburg (FNAL) 2nd PASI Workshop5.Apr. 2013

Fermilab

Six 1-cells tested extensively from 2008– BCP/VT @Cornell, some had add’l prep/tests– Useful information learned, e.g., defect on die– Primarily being used for commissioning and

materials studies now

Six 9-cells received QC shows fabrication is not yet as stable as other vendors Performance is moderate

Tumbling R&D

New Vendor Development: Niowave-Roark


Fermilab

• NR flash BCP’d the six 9-cells – insufficient data to comment• AES flash BCP’d the latest batch of six 9-cell cavities – all

show some pitting but performance is typically good– Does BCP cause the pitting?

• Process not well controlled, e.g., acid flow too fast• Pitting worse on lower surface than upper

– Does material cause the pitting?• Pits re-emerge after tumbling• R&D on sheet corners anticipated

• RI did bulk EP on half of the latest batch (six of twelve)– Performance more likely to improve after heavier “light” EP

• So far, no performance advantage, but potential advantage justifies a controlled promotion of industrial processing

– AES has a new EP machine – Process was qualified on a 1-cell cavity– AES to bulk EP six cavities this year

Vendor Surface Processing


FermilabIndustrial Surface Processing


Fermilab

TB9AES013: Pits observed in all three images, but generally enhanced by EP. Pits are not restricted to just the equator weld or the heat affected zone.

1) Optical inspection of equator weld before EP

2) Photo before electropolishing.

3) Photo after electropolishing ( ~ 120 microns removed)

Cavities Flash BCP’d at Vendor

1

2

3


FermilabCavities Bulk-EP at Vendor

RI bulk-EP removal amount (um)133 153 138 130 152 140

*KEK grinding repair

*


FermilabValue Engineering: FNAL Dressed Cavity

CavityCosts

63-71%

11-12%

11-13%

6-13%

Dressed Elliptical SRF Cavity Fully Burdened

Cost Breakdown*Fermilab Costs

Second PassHPR Reprocess

• Processing is ~ 13% of the cost of a dressed cavity


Fermilab

Estimated FNAL Cost Breakdown

Fully Burdened Cost Breakdown

*Fermilab Costs

• 26%*13% =4% of the cost of a dressed cavity is material removal

• Processing costs dominated by touch labor

19 Ginsburg - NGLS Review Feb 5-8, 2013

Value Engineering: FNAL/ANL Cavity Processing


FermilabValue Engineering: FNAL ILC Cryomodule

ILC Type-3 Cryomodule M&S actual cost

43%

26%

15%


FermilabFNAL CM Assembly Throughput

21

13 days

14 days

9 days

8 days

14 days

5.Apr. 2013 Ginsburg (FNAL) 2nd PASI Workshop

FermilabFNAL Cryomodule Assembly

• CAF infrastructure is fully functional for the 1.3 GHz pulsed cryomodule assembly.

• We have assembled two 1.3 GHz and one 3.9 GHz cryomodules at CAF. Our experience is still too limited to fully assess each step of the assembly and make optimization.

• New assembly tooling will be needed to assemble the 325 and 650 MHz cryomodules but the main infrastructure of the CAF looks adequate to assemble these cryomodules.

• Cavity dressing/qualification and assembly components preparation for cryomodule assembly will probably require some automation in order to increase the throughput for future projects.

• Cryomodule assembly throughput requirements will dictate hiring and training technicians. Training required for CM assembly is lengthy, especially for cleanroom work.

225.Apr. 2013 Ginsburg (FNAL) 2nd PASI Workshop

FermilabILC Industrialization Workshops

• Two ILC industrialization workshops took place, with substantial industrial and lab participation– PAC10 Kyoto satellite meeting

• http://ilcagenda.linearcollider.org/conferenceDisplay.py?confId=4530

– SRF2011 Chicago satellite meeting• http://ilcagenda.linearcollider.org/conferenceDisplay.py?confId=5182

• Discussion topics: niobium material, cavity fabrication, industry regional differences, CM fabrication

• Webpages provide a useful resource


Fermilab


FermilabSummary


ILC has provided a great opportunity for US SRF industrial development Cavity vendor development Cavity processing vendor development

Cavity and cryomodule value engineering exercises are ongoing for future projects

Existing industrialization workshops (ILC) provide a resource for understanding cost reduction targets

FermilabAcknowledgements

• Many thanks to our Fermilab, national, and international collaborators for their hard work and excellent contributions to the cavity and cryomodule development presented here

• Material for this presentation was provided by T. Arkan, J. Kerby*, A. Rowe (FNAL).

*now at Argonne National Laboratory


superconducting rf cavity/cryomodule development at fermilab (industrialization) c.m. ginsburg...

Documents

fermilab ilc cavity

cold mass assembly area

assembly sequence

fermilab bare cavity

cold mass assembly fixture

fermilab industrialization

vacuum vessel assembly

srf cavities