PowerPoint Presentation

Cryomodule Concept for the ODU RF Dipole Crab CavityTom Nicol* - FermilabDecember 10, 2013

* With lots of help from HyeKyoung, Tom J, Shrikant, Ofelia, Luis, et alStill in the early stagesInitial input fromFunctional specification from CERN, especially integration into SPSCavity model from HyeKyoungPresentation from Shrikant at November meetingMeeting with Tom Jones at FermilabIntegration solid models from CERNEmail correspondence with manyetcDecember 10, 20136th LHC Crab Cavity Workshop2RFD cryomodule in SPS

December 10, 20136th LHC Crab Cavity Workshop3Cavity stress at 2.6 bar

Original cavity model from ODUVarious cavity analyses to familiarize myself with the designDecember 10, 20136th LHC Crab Cavity Workshop4Cavity model tuner load

Not sure about this portDecember 10, 20136th LHC Crab Cavity Workshop5Cavity displacement tuner load

~0.6 mm deflection at 10,000 N applied axial loadConsistent with the latest results from ODU which show 18,300 N/mmDecember 10, 20136th LHC Crab Cavity Workshop6Cavity stress tuner load

December 10, 20136th LHC Crab Cavity Workshop7Example of ASME Code analysisMAWP>= 0.2 Mpa at 300 K>= 0.4 Mpa at 2KProtection against collapse from bucklingProtection against cycling loading (fatigue and ratcheting)Protection against plastic collapseProtection against local failure

325 MHz spoke cavity at FermilabDecember 10, 20136th LHC Crab Cavity Workshop8Actual results were:0.24 Mpa at 300 K0.90 Mpa at 2 KDecember 10, 20136th LHC Crab Cavity Workshop9SSR1 linear elastic stress plot

Thanks to Leonardo RistoriEstablished material properties for dressed cavitiesMaterialPropertyElastic ModulusYield StrengthUltimate StrengthIntegrated Thermal Contraction 293K to 1.88K (in/in)(psi) and GPa(psi) and MPa(psi) and MPa293K1.88 K293K1.88 KNiobium15.2E+061045,5003846,00031716,60011487,0006000.001455Ti-45Nb9.0E+066269,00047679,000545N/AN/A0.0019Titanium, Gr. 215.5E+0610740,000276121,00083450,000345162,0001,1170.0015From FESHM guidelines for dressed cavity fabrication part of FESHM Chapter 5031.6December 10, 20136th LHC Crab Cavity Workshop10Testing matrix for cavity materialsMaterialBatch IDRoom temperature77 K4.5 KSample IDYieldUltimateCharpyYieldUltimateCharpyYieldUltimateCharpy Trans-1 Trans-2 Trans-3Trans avgLong-1Long-2Long-3Long avgElastic modulusChemical contentDecember 10, 20136th LHC Crab Cavity Workshop11Initial design featuresIncorporate all fixed constraints, i.e. pipe sizes, locations, etc., initially focused on SPS requirementsDressed cavities supported from the bottomAdapt an end-lever tuner from Saclay or 650 MHz elliptical cavities at FermilabStill undecided about helium vessel material (more analysis needed)Bottom-up assembly similar to FRIB cryomodulesReally wanted a round vacuum vessel, but it just isnt a good fit to the current requirements

December 10, 20136th LHC Crab Cavity Workshop12December 10, 20136th LHC Crab Cavity Workshop13RFD dressed cavity

RFD cold mass assembly

December 10, 20136th LHC Crab Cavity Workshop14RFD cold mass assembly

December 10, 20136th LHC Crab Cavity Workshop15RFD cold mass assembly

December 10, 20136th LHC Crab Cavity Workshop16Input and HOM coupler vacuum bellowsSupport post pocket

December 10, 20136th LHC Crab Cavity Workshop17FRIB cryomoduleRFD cryomodule

December 10, 20136th LHC Crab Cavity Workshop18May want access ports on one or both sidesRFD cryomodule aisle side

December 10, 20136th LHC Crab Cavity Workshop19RFDcryomodule wall side

December 10, 20136th LHC Crab Cavity Workshop20RFD cryomodule end view

December 10, 20136th LHC Crab Cavity Workshop21RFD magnetic shield

December 10, 20136th LHC Crab Cavity Workshop22RFD thermal shield

December 10, 20136th LHC Crab Cavity Workshop23MLI not shownAssembly sequence

December 10, 20136th LHC Crab Cavity Workshop24December 10, 20136th LHC Crab Cavity Workshop25Bypass beamline location

Vacuum vessel stress

1 atm external pressure, 19 mm thick shell, 38 mm thick bottom plate, could be thinner with the use of stiffenersDecember 10, 20136th LHC Crab Cavity Workshop26Vacuum vessel displacement

December 10, 20136th LHC Crab Cavity Workshop27Support post analysis

Heat loads (each support)0.9 W to 80 K0.13 W to 2 K

(assume 1 mm thick composite tube thickness)December 10, 20136th LHC Crab Cavity Workshop28Still much to do on the designLook into switching the positions of the input and HOM couplersDevelop tuner details and ensure compatibility with tuning requirementsLook at cooldown stresses and interaction between the helium vessel and cavityIntegrate the remaining cryogenic piping, including coupler cooling

December 10, 20136th LHC Crab Cavity Workshop29High level schedule Dec 2013

December 10, 20136th LHC Crab Cavity Workshop30Each of these steps implies a lot of other stepsDetermine safety requirements for involved labsFinalize tuning requirements including df/dpDecide on helium vessel materialDecide on vacuum sealing technology, e.g. Conflats vs. aluminum diamond sealsIntegrate devices from others, e.g. couplers and tunersVerify heat load complianceEnsure cavity is compatible with cleaning requirementsDetermine method for in-process frequency adjustment

December 10, 20136th LHC Crab Cavity Workshop31Technical steps (to name a few)Functional Requirements SpecificationEngineering Risk Assessment (to determine extent of following steps)Statement of WorkProject Management PlanTechnical Requirements SpecificationDesign ProcessDesign Review(s)Safety Review(s)Procurement ProcessPerformance Acceptance Test

December 10, 20136th LHC Crab Cavity Workshop32Project requirements (to name a few)December 10, 20136th LHC Crab Cavity Workshop33SummaryWe have resources that can be allocated to cryomodule design and analysisWe have some capability to help with safety analysis if neededContinue working on the conceptual and detailed cryomodule designWork closely with the cavity designers and assist where neededProvide oversight of dressed cavity fabrication as neededContinue filling in more of the details implied by the high level schedule