Cryomodule Assembly Facility (CAF) at Fermilab: Feasibility Overview for Project X & future SRF Cryomodules Assemblies Tug Arkan February 21, 2012

2 Outline Current CAF infrastructure –1.3 GHz Cryomodule Assembly Workflow at Cryomodule Assembly Facility (CAF): Cavity Dressing workflow Cavity String Assembly Cold Mass Assembly Vacuum Vessel Assembly Future CAF infrastructure needed for Project X and other SRF cryomodules assemblies Summary

3 CAF-MP9 CAF-MP9 houses the string assembly clean room, the rail for string assembly under the clean room extending to the cold mass assembly area and the cold mass assembly fixture adjacent to the clean room.

4 CAF-ICB CAF-ICB houses the Vacuum Vessel Assembly area and Final Assembly area including the Big Bertha Fixture.

1.3GHz Bare Cavity Workflow 5 Once the bare cavity reaches the specified gradient at the vertical test stand, the cavity gets into the dressing workflow. This is a current “standard” processing workflow for the bare cavity qualification. Barrel polishing/tumbling is currently studied/evaluated to replace bulk EP step.

1.3GHz Cavity Dressing Workflow 6 This is a detailed workflow currently used for high gradient 1.3 GHz cavities R&D.

1.3GHz Cavity to Helium Vessel Welding 7 Cavity & Helium Vessel on the insertion fixture Cavity being setup in the glove box Completed welds Cavity in the glove box Current Throughput: 2-1/2 days per cavity

Automatic TIG Welder Concept (cavity dressing throughput increase) 8 Courtesy of Chuck Grimm 1.3 GHz cavity 650 MHz cavity 325 MHz cavity -The estimated cost is 200~250 k$ - This setup will significantly reduce the duration of the current welding time in the glove box. -We could probably dress a 650 MHz cavity in a couple of hours MHz should be easier with two circumferential S.S. welds compared to the titanium welds for the 1.3 GHz and 650 MHz cavities

9 Assembly CAF-MP9 Receive dressed Cavities 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

10 Assembly CAF-ICB 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

11 CAF-MP9 Clean Room Cavity String Assembly Clean Room A ~250 square-meter clean room: –Class 1000 ante clean room area: Preparation of the dressed cavities for transportation into the assembly clean room. –Class 10/100 sluice area Parts and Fixtures final preparation to enter the Class 10 assembly area. –Class 100 area Parts and Fixtures preparation for assembly. –Class 10 assembly clean room area: Where the cavities vacuum is vented to interconnect them with bellows. Class 1000 Class 10 Rail Class 100

Cleanroom Infrastructure 12 Vacuum / Gas Manifold Class 1000 cleanroom for the dressed/qualified cavity preparation to enter the cleanroom

13 Rail for Cavity String Assembly Rail length: 3.65 m, 12 rails aligned to each other to 0.1 mm Max allowed load: 1500 lbs. per foot

Cleanroom Highlights State-of- the-art cleanroom optimized for SRF R&D. The cleanroom is fully functional for the SRF R&D. It has been operated and maintained meticulously since it was constructed in We have assembled CM1, CM2 and 3.9 GHz module cavity strings in this cleanroom. We have prepared ~twenty-five 1.3 GHz dressed cavities and one SSR1 dressed cavity for the horizontal test. We have 3 highly trained and experienced cleanroom technicians: The assembly tasks conducted at the CAF cleanroom require extreme care and strict adherence to the cleanroom working protocols. The floor of the cleanroom is raised 2 feet of the building floor. The max allowed floor loading is 500 lbs. per square foot. 1.3GHz dressed cavity weighs ~ 200 lbs. We need to pay attention to the heavier 325 and 650 MHz dressed cavities if we want to store them in the cleanroom on the floor. (Though the assembly rails can support max 1500 lbs. per foot) 14

15 Cavity preparation to enter the clean room Cavity exterior surfaces are wiped with lint free cloth soaked in isopropyl alcohol in the Class 1000 soft wall clean room. (not washed in in the ultrasonic bath) Cavities are then transported in the Class 1000 ante clean room where they are installed on the support posts fixture. Slide the cavities in the Class 10/100 Sluice area for further cleaning to enter the Class 10 assembly clean room: –Wipe with lint free cloth –Blow clean with ionized nitrogen while monitoring the airborne particulates with a particle counter –Continue to clean until acceptable counts are reached Class 1000 soft wall clean room

16 Parts / Fixture / Hardware Preparation Assembly hardware: –Wash in the ultrasonic bath –Blow clean with ionized nitrogen under the Class 10 hood –Bag and transport in the Class 1000 ante clean room –Blow clean with ionized nitrogen while monitoring the particulates count in the sluice area –Transport into the Class 10 assembly Class 10 Hood US cleaner Electro-polished, rolled thread stainless steel studs; silicon bronze nuts

GHz Cavity Support Posts Fixture Cavity is supported through the alignment ring on the beam pipe flange at the coupler end Cavity is supported through the alignment ring on the beampipe flange at the field probe end

18 Cavity Alignment in the clean room X-Y Alignment Fixture: Cavities beam line flanges are aligned to ~0.5mm for the interconnect bellows assembly in the clean room Rotational Alignment Fixture: Coupler position: parallel to earth with respect to the cavity helium vessel lugs

19 String Assembly Gate Valve to Cavity Assembly: –Sub-assembly of the right angle valve –Installation to the support post and vacuum hose assembly –Leak check –Alignment to the cavity beam line flange –Particulate free flange assembly (PFFA) procedures –Assemble the gate valve to the cavity

20 String Assembly (cont.) Cavity to Cavity Assembly with the interconnect bellows: –Assemble vacuum hose to the cavity. Pump down and Leak check. Backfill –Align the interconnect bellows to the cavity field probe end beam line flange –Assemble with PFFA –Align the bellows to the other cavity coupler end beam line flange –Assemble with PFFA

21 Adjustable Table Fixture This fixture is used to align the flanges of the parts that will be assembled

22 Miscellaneous Fixtures Interconnecting Bellows Holder Fixture Gate Valve Holder & Alignment Fixture

23 Cold Mass Assembly Spreader bar fixture is used to support, lower and raise the GRHP String assembly rail is aligned to the center of the spreader bar fixture

Cold Mass Assembly at CAF-MP9 24 Work outside of the clean room before the string was lifted off the rail to the cold mass support: –2-phase helium pipes & bellows welding –Cavity magnetic shields installation –Tuner installation –Cavity insulation installation –Temperature sensors instrumentation and RF cables installation –Cavity helium vessel lugs needle bearings and housings installation –Various leak checks / pressure tests of the helium circuit –Various electrical and RF checks

25 Cold Mass Transport After the cavity string is picked up off the rail and partially assembled to the cold mass support, the cold mass assembly is transported to the Vacuum Vessel Assembly Area at CAF-ICB (~5km from CAF-MP9).

Cold Mass Assembly at CAF-ICB Assembly Tasks: –Put the cold mass on the 4 support spreader bar fixture –Align cavity string to GRHP to 0.1 mm (laser tracker) –Complete the interconnect magnetic shielding assembly –Complete the coupler heat shields intercepts assembly –Complete cooling straps assembly to the cavities HOM –Complete the harnessing of the instrumentation wires & RF cables –Various electrical checks –Weld the magnet current leads to the magnet instrumentation box –Various leak checks of the helium circuit 26

27 Final Assembly The assembly fixture used in CAF-ICB is the Vacuum Vessel Assembly fixture aka “Big Bertha” –a cantilever fixture used to support the cold mass for the remainder of the assembly and then slide the vacuum vessel onto the cold mass

Final Assembly at CAF-ICB Assembly tasks: –Install and weld lower 5K aluminum shields –Wrap 10 layers of MLI –Install and weld 80K shields –Lay and wrap 30 layers of MLI –Trim insulations around main couplers, magnet and cold mass support posts –Slide vacuum vessel onto the cold mass –Align cold mass to the vacuum vessel (laser tracker) –Install warm part of the main power couplers –Route & terminate instrumentations wires and RF cables to the feedthrough flanges –Install coupler pumping lines –Pump down and leak check insulating vacuum 28

29 Cryomodule Transport Fixture to transport completed Cryomodule from CAF- ICB to the ILCTA-NML

Future Cryomodules at CAF 1.3 GHz pulsed cryomodules for ILCTA-NML: –CM3 to CM6, 4 cryomodules, 1 module per year throughput limitation due to high gradient (35MV/m) cavity specification. CM3: 2013; CM4: 2014; CM5: 2015; CM6: MHz CW SSR1 cryomodule for PXIE: –1 module for assembly in GHz CW cryomodules (20), 3.9 GHz cryomodule (1) for NGLS (potential work) –20 cryomodules in 2 years, ~1 module per every 6 weeks 325 MHz CW SSR1 (1), SSR2 (4) for Project X 650 MHz CW LB (7), HB (19) for Project X 1.3 GHz pulsed cryomodules (28) for Project X 30

SSR1 cryomodule 31 Proposed Assembly Workflow: 1.8 cavities, 4 solenoids: Assemble in the CAF-MP9 cleanroom using the existing rail system and new tooling to support each component on the rails. New tooling to align and assemble the interconnecting bellows between the components. 2.Roll the cavity string out of cleanroom. 3.Pick up the string of the cleanroom fixtures with a new cage tooling and the existing red spreader bar fixture and transport to CAF-ICB 4.Assemble cavity string on the cold mass support platform in ICB (new tooling) 5.Complete & Align the cold mass assembly (new tooling) 6.Insert the cold mass into the vacuum vessel (new tooling) 7.Assemble warm end of the couplers (new tooling)

650 HB Cryomodule 32 Proposed Assembly Workflow: 1.8 cavities: Assemble in the CAF-MP9 cleanroom using the existing rail system and new tooling to support each component on the rails. New tooling to align and assemble the interconnecting bellows between the components. 2.Roll the cavity string out of cleanroom. 3.Assemble cold mass in CAF-MP9 (new tooling) 4.Lower the GRHP and assemble the string to the GRHP 5.Transport cold mass to CAF-ICB (new tooling) 6.Complete & Align the cold mass assembly (new tooling) 7.Insert the cold mass into the vacuum vessel (we can probably use Big Bertha) 8.Assemble warm end of the couplers (new tooling)

Cleanroom throughput - I CAF-MP9 cleanroom infrastructure is setup with a throughput goal of 1 cavity string assembly per 13 days (~3 weeks) with the assumption day all the needed cavities, parts, assembly hardware are pre-cleaned and ready to be used in the Class 10 cleanroom: –Alignment of the cavities for string assembly (1 day) –Assemble cavity #1 with gate valve (1 day) –Assemble 4 cavities with interconnecting bellows (3 days) –Leak check 4 cavities sub-assembly (1 day) –Assemble remaining for cavities (3 days) –Assemble magnet sub-assembly (1 day) –Assemble magnet sub-assembly to the cavity string (1 day) –Leak check string (2 day) –Prepare string for roll-out of the cleanroom 33

Cleanroom throughput - II To increase the throughput: 1.Add a second team of cleanroom technicians (3 techs) 2.Double / modify the current vacuum/gas system for the cleanroom 3.Modify the rail system in the cleanroom so that cavity support fixture sliding bearings can be loaded onto the rail in Class 10 cleanroom If all the above 3 steps are done; the assembly time can be cut to 2 weeks per string with a continuous (finish one string, roll out from the cleanroom, finish the second one, roll out of the cleanroom and so on) workflow. If all the above 3 steps + adding a second rail system are done, the assembly time can be cut to 1 week per string with a continuous workflow. Adding a second rail system is not a trivial solution and requires a major costly (250~300 k$) modification to the cleanroom. 34

Cleanroom throughput - III To increase the throughput: –Assembly hardware (studs, nuts, washers, gaskets) cleaned to UHV + particulate free to Class 10 standards and individually bagged for storage prior to entry to the cleanroom –A washing machine for the cavities exterior surfaces, assembly fixtures, peripheral assembly components: Load the machine with dirty parts from the production floor Wash and dry cycles complete Unload the clean parts from the Class 10 area 35 Washing Machine used at CEA-Saclay cleanroom for the XFEL cryomodules assembly Bagged clean assembly hardware

Cleanroom Throughput- IV We have currently 3 trained, experienced cleanroom technicians. Lead technician was initially trained by observing cleanroom work at DESY, JLAB. Then he trained the second lead technician at FNAL after the CAF-MP9 cleanroom infrastructure was setup. CAF cleanroom team training got completed when CM1 was assembled at FNAL with the assistance of the DESY cleanroom personnel. Overall, it took approx. 2 years to have 2 fully qualified cleanroom technicians. We tried to hire more cleanroom technicians assuming that semiconductor industry is not doing as well as before and there should be enough candidates looking for cleanroom jobs. When we started to interview and hired a contract tech to try out, we came to realization that semiconductor type technicians lack the skills of a good mechanical tech and they cannot be trained to gain mechanical aptitude skills. The 3 rd technician working in the cleanroom was pulled from the outside CAF assembly team. 2 main cleanroom technicians trained him over 1 year and at the end of the second year of becoming a cleanroom tech, he was deemed fully trained to work directly on the SRF components assemblies. In order to ramp out the CAF cleanroom throughput, we need to find good background mechanical techs who are willing to learn the cleanroom skills and train them at least 1.5 year before they are fully qualified to work on SRF components. 36

1.3 GHz Cold Mass Assembly Throughput - I Cold mass assembly on the cold mass assembly fixture at CAF-MP9 (14 days) –2-phase helium pipes cutting & bellows welding (2 days) –Cavity magnetic shields installation (1 day) –Tuner installation (2 days) –Cavity insulation installation (1 day) –Temperature sensors instrumentation and RF cables installation ( 3 days) –Cavity helium vessel lugs needle bearings and housings installation (2 days) –Various leak checks / pressure tests of the helium circuit (1 day) –Various electrical and RF checks (2 days) 37

1.3 GHz Cold Mass Assembly Throughput - II Cold mass assembly on the cold mass assembly fixture at CAF-ICB ( 9 days) –Alignment (3 days) –Magnet current leads soldering (1 day) –Magnet current leads welding (1 day) –Interconnect magnetic shields assembly (1 day) –Wires/Cables check (1 day) –Wires/Cables harnessing (1 day) –Move the cold mass to Big Bertha fixture (1 day) 38

1.3 GHz Cold Mass Assembly Throughput - III Cold mass assembly on Big Bertha Fixture at CAF-ICB (8 days) –Install and weld lower 5K aluminum shields (1 day) –Wrap 10 layers of MLI (0.5 day) –Install and weld 80K shields (1 day) –Lay and wrap 30 layers of MLI (1.5 days) –Trim insulations around main couplers, magnet and cold mass support posts (1 day) –Slide vacuum vessel onto the cold mass (1 day) –Align cold mass to the vacuum vessel (laser tracker) (2 days) Final Assembly; cryomodule on the cement blocks at CAF-ICB (14 days) –Install warm part of the main power couplers (8 days) [semi cleanroom] –Route & terminate instrumentations wires and RF cables to the feedthrough flanges (3 days) –Install coupler pumping lines (1 day) [semi cleanroom] –Pump down and leak check insulating vacuum (2 days) 39

Recap of Current Throughput days 14 days 9 days 8 days 14 days

1.3 GHz Cold Mass Assembly Throughput - IV Total days needed to assemble 1.3 GHz pulsed cryomodules = 45 days CAF cold mass assembly group has 2 fully trained experienced technicians and 1 trained technician from another group helps CAF cold mass assembly team during module assembly. Total mechanical techs working on the cold mass assembly = 3 In order to increase the throughput to 1 module assembly per 6 weeks: –2 weeks for string assembly in the cleanroom –4 weeks (20 days) for cold mass assembly outside of the cleanroom –In order to reduce the 45 days to 20 days: increase the CAF cold mass assembly group technician count to 6. The training time for a cold mass assembly technician is less than a cleanroom technician. I took approx. 6 months to train the current CAF cold mass assembly technicians. The assumption is that both the CAF cold mass assembly areas and CAF cleanroom are simultaneously being used in order to keep up with the throughout. Taking into account that certain tasks are not effort driven and the duration of the task cannot be reduced by adding more technician resources and also taking some riskier tasks can take more time that estimated duration, duplicate cold mass assembly fixtures and areas were already setup at CAF facilities. 41

Summary CAF infrastructure is currently fully functional for the 1.3 GHz pulsed cryomodules assembly. We have assembled two 1.3 GHz and one 3.9 GHz cryomodules at CAF. Our experience is still 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. Cryomodule assembly throughput requirements will dictate hiring and training technician resources. The training required for the SRF assemblies are lengthy, especially for the cleanroom work. 42