SCH Controls Readiness Review- Cryostat Nov 4-5, 2015 Kurt Cantrell

Overview Cryostat Overview Quality Control - Manufacturing Procedures Quality Control - Testing Cryostat Design Structural Design Requirements Risk Assessment 2

Cryostat Overview 3 Cryostat Performance Goals: Provide vacuum insulation for the outsert coil Provide radiation barrier for the outsert coil Provide for cryogen services, instrumentation and power feedthrus for the outsert coil Support cold mass weight Support coil misalignment loads Support fault forces Provide for interface with outsert coil, housing and hydrant Structural Design Criterion ASME PVC Section VIII, div. 2 ASME B31

Cryostat- Manufacturing Procedures 4 Cryostat was fabricated at Criotec Impianti in Chivasso, Italy (not a holder of ASME PVC stamp) Fabricated to NHMFL drawings which were designed to the ASME B&PVC section VIII, div. 2 and ASME B31 Communication Videoconference every two weeks Frequent traffic Personnel were present to check for manufacturing issues and during assembly fit-up Personnel were present during important test stages Drawing review Various drawing revisions were made by Criotec Change to metric material thickness or other European standards Minor material property changes Facilitate manufacturing to how they are accustomed Thermal bore tube shield design to follow the style implemented for the HZB cryostat Tracking Engineering Changes A drawing tracking form is filled out to track changes A change to the revision number is made in the drawing block A model is sent to NHMFL for approval

Cryostat- Manufacturing Procedures 5 Example of Engineering Tracking Form

Cryostat-Quality Control -Testing Assembly DescriptionTest DescriptionLocation Major structural partsNDE of weldsCriotec Impianti Vacuum VesselHelium leak check at room temperature to 3E-9 mbar-l/sCriotec Impianti Warm Bore TubeHydrostatic pressure test to 67.5 barg (1.3x MAWP)Criotec Impianti LN2 Shields Plumbing and Bore Tube Shield Hydrostatic pressure to 7.5 barg (1.3x MAWP)Criotec Impianti LN2 Shields Plumbing and Bore Tube Shield Helium leak check at 77 K to 3E-9 mbar-l/sCriotec Impianti SHe and LN 2 ServicesThree thermal cyclesCriotec Impianti SHe ServicesHydrostatic pressure to 27 barg (1.3x MAWP)Criotec Impianti LN2 Shields Supply/Return (and associated plumbing) Hydrostatic pressure to 7.5 barg (1.3x MAWP)Criotec Impianti LN2 Tank (and associated plumbing)Hydrostatic pressure to 3 barg (1.3x MAWP)Criotec Impianti SHe and LN 2 ServicesHelium leak check at room temperature to 3E-9 mbar-l/sCriotec Impianti Insert housing/hydrantHydrostatic pressure test to 67.5 barg (1.3x MAWP) RV Industries Completed SHe circuitHelium leak test by pumping on vacuum vessel while circuit under 150 psiNHMFL Completed LN2 circuitHelium leak test at 15 psi differentialNHMFL Vacuum vesselHelium leak testNHMFL 6 Tests Performed Post Fabrication

Cryostat Design-Vacuum Vessel 7 Requirements High Vacuum Inside Fault Load, Strongback Service penetrations Design Welded/Bolted Construction Warm O-Ring Seals

Cryostat-Mechanical Loads 8 Fault Load Path

Cryostat Design-Bore Tube/Strongback 9 Requirements Fault Load Radial Stiffness for 40 Bar Over Pressure Return water Operation-30 bar water inside High Vacuum Outside Design Double Wall Machined Weldment/Forging Axisymmetric Water Supply Water Return Fault Load

Cryostat Design-Bore Tube/Strongback FEA 10 The SCH insert housing is a double wall structure containing coils inside, and supported by cryostat main frame structure Cooling water enters in the housing, passing through coils, and flows out in between the double walls FEA model is extracted for cornerstone structures along the loading path Structural load path

Cryostat Design-Bore Tube/Strongback FEA 11 Structural meshes scale factor, 50 Boundary conditions Rib and weld function in difference load scenarios

Cryostat Design-Bore Tube/Strongback FEA: Deflection Example 12 1)During normal operation, the distance between double walls will shrink <0.01mm in the top and shrink <0.05mm in the bottom 2)Outer wall will move mm toward inner wall in the top, and 0.044mm toward cryostat in the bottom 3)Inner wall will move mm toward outer wall in the top and 0.088mm toward outer wall in the bottom Normal operation radial deflection 1)In current model, during normal operation the length of the outer wall shrink approximately 0.034mm as well as the outer wall will shrink 0.056mm (the compliance of the threaded ring and the cryostat are not considered) 2)The offset between the D coil and the outsert is approximately 0.022mm. Normal operation axial deflection

Cryostat Design-Insert Hydrant FEA 13

Cryostat Design-Cold Mass Support Columns 14 Requirements Axial Stiffness Fault Load (Tension/Compression) Minimum conduction load 300 K to 4 K Design 88 K Intercept Integral Manifolds Machined Weldment 1.3 watts/Column to He 7 watts/Column to N2 Buckling stability of the Columns Tresca stress FEA detail

Cryostat Design-Warm Columns 15 Requirements React Vacuum Loads Weight System Ground Design Constant Cross-section 88 k Shield Bolted w/ adjustment Machined Weldment The vacuum load to the SCH structure is supported by cryostat OD wall, warm columns, and the bore tube. From FEA, the bore tube share 19% of the total vacuum load.

Cryostat Design-Warm to Cold Links 16 Analysis -Linear stress/strain -Magnetic stiffness

Cryostat Design-Permanent Frame (External consultant David H. Melvin, Inc. analysis results) 17 Analyzed to conform to the AISC design code by licensed State of Florida PE Loads considered: -Vertical load of ~ 220 kN -Side load of ~ 20 kN Displacement (in) Frame stress plot Known loads external: Side loads: 5 kN: 10 mm offset from iron shield Cooling water loads (load share with plumbing) 26.6 kN bus bar load Vertical loads: System weight of 205 kN downward 12 kN downward due to offset with iron shield 38 kN downward due to rebar in the floor Action options: -Re-analyze frame considering all loads -Proof test frame using known side loads

Cryostat-Venting Safety 18 Protective barrier around HTS leads and cryogenic services/vents 6” pipe weight-loaded vent on vacuum vessel for loss of cryogen containment GN2 vent line carries all GN2 outside

Cryostat-Risk Assessment 19

Thank You!