Status and plans for the ILC cryomodule design

1. Status and plans for the ILC cryomodule design Tom Peterson, Fermilab TESLA Technology Collaboration Meeting Frascati, 6 December 2005

2. TTF cryomodule is our reference Tom Peterson

3. TESLA-style module information . . . • http://ilc.desy.de/e627/e634/e730/e745/index_eng.html • Links to talks presented by Lutz Lilje, Axel Matheisen, W.-D. Mueller, Bernd Petersen, Nick Walker, and others at our December 6 - 7, 2004, module meeting at DESY • http://lcdev.kek.jp/ILCWS/ • “First ILC workshop,” November 13 - 15, 2004 at KEK • http://tesla-new.desy.de/content/index_eng.html • DESY TESLA page with link to the TESLA Design Report and other information including talks and posters from the March 2004 ITRP visit Tom Peterson

4. Sources of Information • Bernd Petersen, Lutz Lilje, Axel Matheisen, Nick Walker, Hans Weise, and others (DESY) • Carlo Pagani (INFN) • Terry Garvey (LAL-Orsay) • Tom Nicol (Fermilab) • Don Mitchell (Fermilab) • John Weisend (SLAC) • TESLA TDR (March 2001) • And others! Tom Peterson

5. Some History of Changes in Design Features for TTF Cryomodule • Three “generations” of TTF cryomodule designs • TTF-I was module #1 • TTF-II was modules #2 and #3 • TTF-III is modules #4 - #8 • TDR called for some significant changes from all of the above such as a longer module with 12 cavities per module • Next -- TTF III is our baseline design • X-FEL modules will differ in some details from TTF type III • ILC modules will begin as a few “type III+” prototypes, which are essentially type III with the quad at 2 K and supported like a cavity • Planning has begun for the next generation ILC module design, type IV, based on the type III+ design Tom Peterson

6. Tom Peterson

7. Features of type III cryomodule • Allows for fixed couplers • Invar rod and roller bearings allow cavities to remain axially fixed while the 300 mm tube shrinks • Smaller cross section results in standard pipe size for outer vessel • Axial position of last support changed to stiffen structure near quadrupole Tom Peterson

8. Cryomodule III model -- helium vessels in the vacuum vessel CAD model based on DESY design imported and modified by Don Mitchell, Fermilab Tom Peterson

9. Cryomodule III model -- helium vessels in the vacuum vessel with input couplers and quadrupole CAD model based on DESY design imported and modified by Don Mitchell, Fermilab Tom Peterson

10. We have a general consensus regarding what needs changing • Based largely on TTF experience, but also Jlab and others • Consensus collected by working groups at meetings, including but not limited to • SLAC (14 - 16 Oct 2004) • KEK (13 - 15 Nov 2004) • DESY (6 - 8 Dec 2004) • Snowmass (August 2005) • SMTF collaboration meeting (5 - 7 Oct 2005) Tom Peterson

11. Type IV cryomodule will includethe following features from Type III+ • 8 cavities per module • Same cooling scheme and cryogenic system concept • Same vacuum vessel diameter and 300 mm pipe diameter • Nearly the same pipe locations and arrangement • Same cavity centerline location relative to vacuum vessel • Same support posts • Same thermal shields concept, although coupler port locations move • Same cavity support detail (300 mm header as structural backbone with cavities held by roller bearings and invar rods) • Same input coupler (at least in terms of mounting and interface to vacuum vessel, cavity, and thermal shields) Tom Peterson

12. Helium vessel supports Tom Peterson

13. Support posts Tom Peterson

14. Thermal shield installation Tom Peterson

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16. ILC cryogenic system overview • Saturated He II cooled cavities @ 2 K • Helium gas thermal shield @ 5 - 8 K • Helium gas thermal shield @ 40 - 80 K • Two-phase line (liquid helium supply and concurrent vapor return) connects to each helium vessel • Two-phase line connects to gas return once per module • A small diameter warm-up/cool-down line connects the bottoms of the He vessels (primarily for warm-up) • Subcooled helium supply line connects to two-phase line via JT valve once per “string” (~12 modules) Tom Peterson

17. TESLA cryogenic unit Tom Peterson

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19. Type IV cryomodule will differ from type III+ in the following general areas • Cavity iris-to-iris spacing reduced to 283 mm • Reduces length from 12.20 to about 11.8 m, get ~0.75 packing • Slow tuner modified to allow closer cavity-to-cavity spacing (could mean switching to blade tuner design, but choice still open) • Fast tuner -- new design • Quad/corrector/BPM package under center post, hung from 300 mm tube, not on rollers (diverging from X-FEL) • Two major module types, one with quad and one without Tom Peterson

20. More differences of Type IV cryomodule from type III+ • Interconnect features modified to accommodate input coupler at end of cryostat • Quad current leads may be new and different, with local impact on thermal shields and vacuum vessel ports • Provisions for quad power lead connection at center of module • Some pipe sizes will be increased for lower pressure drops with high flow rates -- would like to retain long cryogenic unit lengths up to limit of 300 mm pipe and cryo plants. Present effort includes re-analysis of heat loads, flow rates, and cryogenic system thermal process. Tom Peterson

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22. Cavity Interconnect Tom Peterson

23. Module predicted heat loads Tom Peterson

24. ILC cryogenic system much larger than TESLA 500 • 8 cryogenic plant locations • Approximately 5 km spacing • Each location with 2 cryogenic plants of about the maximum size -- each plant equivalent to about 24 kW at 4.5 K • Each plant about 6 MW “wall plug” power • ILC cryogenics about 100 MW total Tom Peterson

25. Module pipe sizes increase Tom Peterson

26. (Increase diameter beyond X-FEL) (Increase diameter beyond X-FEL) (Review 2-phase pipe size and effect of slope) Tom Peterson

27. Some critical open design issues • Quad/corrector/BPM package is a major unknown right now and goes into the heart of the module • Tuner details, slow and fast, but especially fast tuner • Vibrational analysis, which will be compared to measurements for verification of the model for future design work • Development of module and module component test plans • Verification of cavity positional stability with thermal cycles • Design of test instrumentation for the module • Robustness for shipping, analysis of shipping restraints and loads, shipping specifications • Active quad movers(?) A complication Tom Peterson

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30. Blade tuner concept Tom Peterson

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32. Other open design issues • Design for manufacturability, ease of assembly, and cost reduction are always considerations • Part of the type IV design effort will also be a consideration of other options • particularly with respect to quad location and support • but also perhaps with respect to tuners and/or other features • level of effort on these options will be dictated by our manpower and schedule. Tom Peterson

33. Organization of effort • An international effort • Need division of tasks to make best use of our resources • Minimize duplication of efforts • Take advantage of ideas and expertise • Pursue options with parallel efforts • Each institution has limited resources • Work has begun • Fermilab has organized a group to do type IV design, other labs have also expressed interest and/or begun Tom Peterson

34. Type IV probable schedule • Design module -- 12 - 24 months (2006 - 2007) • Magnet/BPM package • Tuners, etc. • Integrate into module design • Build and test -- 12 - 18 months (2007 - 2008) • In addition to module, need module test stand and test facility! • Total 2 to 3 1/2 years, depending on scope of work and availability of resources. Tom Peterson

35. X-FEL Modules • 100+ modules will be industrially produced • Brings us to the level of manufacturing quantities • Some differences from ILC, but much of module design and manufacturing is the same • Cavity supports, thermal shields, MLI, vacuum vessel assembly, internal piping, etc. • X-FEL experience will be important and valuable part of ILC module development • X-FEL module effort will stay ahead of ILC effort • Remain in close contact and take advantage of similar designs, experience, and industrial input to design Tom Peterson

36. After Type IV--> increasing quantities • Experience with large quantities of SC magnets follows an old engineering “rule” (factors of 10) • 1 prototype • 10 pre-production prototypes • 100 first production run (X-FEL!) • Not “throw-aways” but slower production, still making adjustments, relatively large fraction of reject/rework • 1000 full production run • There are design changes and manufacturing method changes at each stage Tom Peterson

37. Industrialization, impact on design • As we move to production of quantities of modules in industry, the design will continue to change • Reduction of required labor • Less costly materials • Less costly manufacturing of components • Design for more efficient assembly Tom Peterson

38. Type IV is not the (final) ILC design • Test results of types III and IV will teach us a lot • There will be some choices beyond type IV from parallel development efforts • Industrialization will have a significant impact on the design • Type IV is the next step in module design for ILC Tom Peterson