1. Prototype Cryomodule FDR Ken Premo 21 – 22 January 2015 High Power Coupler Design

2. 2 Outline LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 Introduction Background Coupler design basis Power Coupler Design and Integration Mechanical design details Integration into cryomodule Thermal interfaces to cryomodule RF connections Coupler tuner Work status summary

3. Introduction 3 LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 Background SLAC is responsible for the power coupler order (280 total) Decisions are made by SLAC with input from partner labs SLAC has created a full set of drawings based on DESY drawings Engineering Specification Document (ESD) has been completed Interface Control Document (ICD) has been completed Procurement Readiness Review has been completed Request for Pricing (RFP) has been submitted to vendors Coupler design basis TTF3 type with some modifications Due to schedule constraints existing FNAL ILC couplers were modified for use by the project

4. 4 Power Coupler Design and Integration LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 TTF3 Type power coupler based on DESY design Cold end Warm end

5. 5 Power Coupler Design and Integration LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 Modifications/Design changes (from TTF3) Cold end -Antenna length shortened by 8.5mm -CF100 55K shield mounting surface (new production) Mounting surface area and bolt size increased to improve thermal contact and heat transfer to 55K shield -Design change to be incorporated for future production -Some testing remains to confirm final design (bench and HTS) -No impact to cryomodule design Prototype units may utilize “enhanced” contact area (copper sink) -Not enough time to incorporate design changes for new production cold ends, must use modified colds and maybe sink -Testing currently underway to confirm effectiveness -No impact on cryomodule design

6. 6 Power Coupler Design and Integration LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 Modifications/Design changes (from TTF3) Cold end Mounting surface Shorten tip By 8.5mm

7. 7 Power Coupler Design and Integration LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 Modifications/Design changes (from TTF3) Copper sink for enhanced thermal contact (if needed) OFHC copper sink SS washer

8. 8 Power Coupler Design Overview LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 Modifications/Design changes (from TTF3) Warm end -Prototype cryomodules will use newly manufactured warms -Increased Cu plating thickness on inner conductor Increased from 30 micron to 150 micron to reduce bellows temperature -Additional threaded hole to be added to mount transportation support if it is required Will be added for new production runs of couplers Transportation support will be incorporated on prototype cryomodules Design details not finalized, but this will have no impact on cryomodule design

9. 9 Power Coupler Design Overview LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 Modifications/Design changes (from TTF3) Warm end Increase Cu plating on Inner conductor from 30 to 150 micron Transportation support

10. 10 Power Coupler Design and Integration LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 Integration into cryomodule Integration into cryomodule is the same as for CM2 Same coupler geometry as ILC and CM2 -Lengths of cold and warm sections are the same -Same flanged connections -Same installation procedure Coupler cold end connection to cavity utilizes aluminum diamond seal Warm end connection via O-ring sealed vessel flange Coupler warm end vacuum by common pumping line -TSP and Ion pump utilized for coupler warm vacuum -Coupler warm ends will each have an all metal valve (to isolate vacuum space if required for repair) -Pumps shipped with cryomodule, line under vacuum

11. 11 Power Coupler Design and Integration LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 Integration into cryomodule, same geometry as CM2 55K 5K Cavity connection Pump line Vacuum flange Same geometry

12. 12 Power Coupler Design and Integration LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 Integration into cryomodule Common pumping line TSP and Ion pump location

13. 13 Power Coupler Design and Integration LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 Thermal interfaces to cryomodule There are two thermal interfaces to cryomodule -5K intercept on cold end bellows -55K intercept on cold end CF100 flange Location of thermal interfaces has not changed from TTF3 CW operation requires improved heat transfer away from coupler, particularly the CF100 flange -Initial configuration testing indicates heating of CF100 flange as well as the inner conductor -Interface design includes improvement to the entire heat flow from coupler to cold sink Cryomodule thermal studies currently underway at FNAL and ANL will provide input for thermal interfaces final design No impact on cryomodule design

14. 14 Power Coupler Design and Integration LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 Thermal interfaces to cryomodule

15. 15 Power Coupler Design and Integration LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 Thermal interfaces to cryomodule 5K intercept Interface design -Same design as used on CM2 -Interface consists of aluminum shield clamped on cold end bellows copper ring -Copper braids take heat from shield to 5K line (bolted connection) Braid design not yet complete -Design will include high quality engineered braids, as short as feasible -Connections will utilize indium for better thermal contact -Analysis will determine braid cross-section, length, etc. -These details will not impact cryomodule design

16. 16 Power Coupler Design and Integration LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 Thermal interfaces to cryomodule 55K intercept Interface design -Same basic design as used on CM2 -Interface consists of aluminum shield bolted to back of CF100 flange using M6 screws -Copper braids take heat from shield to 55K outer shield (bolted connection) Braid final design specification not yet complete -Design will include high quality braids, as short as feasible -Connections will utilize indium for better thermal contact -Analysis will determine braid cross-section, length, etc. -Shield on CF100 flange may require improvement (TBD) -These details will not impact cryomodule design

17. 17 Power Coupler Design and Integration LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 Thermal interfaces to cryomodule Bolted Bolted connections Aluminum shield clamped to Copper ring Braid Aluminum shield bolted to CF100

18. 18 Power Coupler Design and Integration LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 RF Connections Waveguide SLAC responsible for waveguide procurement Same waveguide interface configuration as CM2 Waveguide oriented facing upwards Same waveguide mounting brackets as CM2 Waveguide drawings are currently being created by SLAC Waveguides will be procured separately from couplers This procurement will not impact cryomodule design

19. 19 Power Coupler Design and Integration LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 RF Connections, waveguide Waveguide facing up Mounting bracket

20. 20 Power Coupler Design and Integration LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 RF Connections Coupler pickup ports Same port locations as TTF3 type used on CM2 1 e-pickup on cold end 2 e-pickups, an 1 optical port on warm end Coupler warm ends will arrive with feedthroughs Cables will be routed through the vessel vacuum space and terminate at feedthrough flanges

21. 21 Power Coupler Design and Integration LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 RF Connections, coupler pickup ports E-pickup (warm) E-pickup (cold end) E-pickup (warm) Optical port

22. 22 Power Coupler Design and Integration LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 Coupler Tuner Motor Two methods for coupler tuning, manual and motorized Motorized design exists at FNAL (remotely controlled) Same as used in CM2 Current configuration is to ship with manual tuners (knob) -It is possible to retrofit the cryomodules with motorized tuners at a later date if it is deemed necessary -If future decision is to use motorized tuners, value engineering should be done to reduce cost -Decision does not impact cryomodule design Motorized tuners will be used on cryomodule test stand -After cryomodule testing, motorized tuners will be replaced with manual tuners prior to shipment

23. 23 Power Coupler Design and Integration LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 Coupler Tuner Motor Limit switch Motor Position transducer

24. 24 Work Status Summary LCLS-II Prototype Cryomodule FDR, 21 - 22 January 2015 Coupler design 95% complete (my estimate) -ESD, ICD,RFP completed -Minor changes (if required) will not impact cryomodule design Coupler Integration into cryomodule is complete -Coupler is integrated similar to CM2, same geometry -No changes to tooling, installation procedure Thermal Interfaces not fully completed -Mounting locations are set -Braid design will be finalized after testing and analysis completed -Some minor design details may be required for 55K shields -Final design details will not impact cryomodule design RF connections are set -SLAC responsible for waveguide, no impact on cryomodule design -Pick ups are the same as CM2, design is complete Tuner motor design is complete, to be used on test stand only