NCSX VACUUM VESSEL PL Goranson Comprehensive Final Design Review May 05, 2005 Vacuum Vessel Supports Heating/Cooling System NCSX

Talk Overview STATUS VACUUM VESSEL SUPPORT DESIGN VACUUM VESSEL HEATING/COOLING SYSTEM DESIGN ISSUES CONCLUSION

NCSX Status Drawings Vacuum Vessel Coolant Tube System Drawings checked, not signed Vacuum Vessel Coolant Header Assembly Drawings checked, not signed Vacuum Vessel Supports Vertical support rod drawings checked, and signed, not released Lateral support drawings checked and signed, not released Vacuum Vessel NB Port Metal Seals and Seal Template Drawings complete, template procured, rings in fabrication Vacuum Vessel Heating/Cooling System & Diagnostics Top Assembly 50% complete; not required for procurement ICD ICD Vacuum Vessel and Modular Coil Assembly Clearances not signed ICD Insulation Complete ICD VV/Cryostat Coolant Tube Interface Complete ICD VV Local I&C Complete ICD VV Magnetic Diagnostics Complete ICD VV Grounding not signed ICD VV Cooling/Heating Requirements Complete ICD VV Port Resistance Heaters Complete ICD VV Diagnostic Port Allocation and Orientation Complete

NCSX Status Continued DAC NCSX VV Local Thermal Analysis Complete NCSX Vacuum Vessel Heating/Cooling Distribution System Thermo-hydraulic Analysis not signed NCSX Vacuum Vessel Heat Balance Analysis Complete NCSX Vacuum Vessel Support Rod Analysis Complete NCSX Diagnostic Port Flange Weld Stress Resulting From Loss of Power Fault Condition Complete NCSX Port 4 Weld Stress During Bake-out Complete NCSX Design Basis Analysis VV Structural Analysis/Seismic Analysis not signed Coolant Tube Build To Specification Draft complete, not signed VV SRD Complete FMECA Draft commented, not signed CHITS Outstanding chits from PBR resolved

VV Supports NCSX

VV Support Design Overview NCSX Six overhead support rods carry weight of VV Lateral supports, 120 o apart, react lateral and out-of plane loads -Three take CW load (toroidal) -Three take CCW load (toroidal) -Two take radial load - Four take overturning moment Six lower rods react vertical magnetic loads

VV Support Loads NCSX VV Weight 24,000 lbs Including flange extensions, covers, and NB Transition Ducts Diagnostic weight (per ICD)10,750 lbs Lateral out-of plane (radial)? Lateral vacuum radial 3,200 lbs Rotational (toroidal) magnetic0 (halo?) Vertical magnetic loads ± 16,800 lbs Future PFC internals13,250 lbs

VV Support Capability NCSX Critical component is commercial rod end. Nominal dead load, including diagnostics and PFC internals is 8,000 lbs each. Assumes no lower support rods. Rod end ultimate load is 29,300 lbs –Safety factor is 3.7 static, 3.41 during vertical disruption. –Failure mode is permanent deformation, not catastrophic separation. Lower supports could potentially remove 2,840 lbs from each upper support.

Upper Support Rod NCSX Self-aligning design permits thermal growth –MC shell/VV relative movement 5/8”(radial) –shell end is spherical nut/washer –vv end is commercial spherical rod end/threaded lug Adjusted for nominal VV height at 40 C Shell end insulated (thermally and electrically) with G-11CR washer/spacer Titanium alloy rod for high strength, low thermal conductivity, low permeability ¾” diameter

Upper Support Rod Drawing NCSX

Lower Support Rod NCSX Six units react magnetic loads from VV VV end identical to upper support MC end is self-aligning & spring loaded - suspended between Bellville Washer stacks with 0.43” stroke - self-contained subassembly - both upward and downward preload adjustable - permits relative thermal growth during bakeout MC end insulated with G-11CR washer/spacer Titanium rod for high strength, low thermal conductivity, low permeability

Lower Support Rod Drawing NCSX

Lateral Support NCSX Design Requirements Permit radial and vertical growth React lateral, radial imbalance forces Adjust lateral & rotational alignment of vessel Electrical isolation for VV Baseline Design Change FDR design reacted loads from pads on NB transition duct into shell mounted pads MIE does not have NB Ducts FDR DESIGN

MIE Lateral Support Design NCSX Design Features Modification kit reacts load into NB blankoff flange Utilizes baseline MC pads with no changes Retrofit onto NB blankoff port –installed in field MIE DESIGN

Support Rod Temperature Distribution NCSX Thickening shell end insulation reduces gradient, raises end, average temperature Baseline is 0.125” Loss is only 5.2 watts VV Shell 0.5 inch insulation around rod G-10 on end Losses range from 3.2 w to 5.2 w " 0.5" 0.25"

Heating/Cooling System Design NCSX

Coolant System Design Status Tubing drawings checked – 5/16” O.D. 316L annealed stainless tubing – Held with weld studs, clamps, and Grafoil® gaskets Helium Supply/Return Header and Support drawings checked Tubing thermal analysis complete - Thermal performance acceptable - Thermal coef. mismatch not a concern total differential growth only 0.2” in 17 feet. temperature ramped during bakeout gaskets permit movement Discussions with tube bending vendors are in progress Draft build-to specification for Coolant Tubes complete, in comment cycle NCSX

Coolant Tube Installation

Tubing Design Concept Reflects vendor comments Tube tolerance requires robust design mounting clip. Installation of studs must be done at assy of tubes on to VV. Vendor will work from xyz coordinate table, not models. NCSX

Mounting Clip Design Compensates for misalignment in tube pair. + 1/16 lateral (each) + 1/8 vertical (each) Utilizes self aligning nut. Maintains 1/8” clearance for magnetic loops. NCSX

Vertical Port (12) Tube Supports One support near VV - the flange end is supported by header Uses commercial (Jiffy) clips on elevated mount plate - permits ½” insulation under the tubes. - maximizes routing space for cables/wires No gasket - decouple thermal load NCSX

Tube Fabrication Vendor can not fab in one piece. –Tubes hit bender or floor before completion. 3-4 piece design will be used. –Body tube –Upper Port Tube –Lower Port Tube –Possibly a mid-plane splice Weld together at assembly Only 2 configurations of Port Tubes are required. NCSX

Typical CNC Bending Machine Bends clockwise and counterclockwise rotation. Simultaneous head rotation around part, with collet rotation. Stacked bend rollers with die shifter can bend tubes up to four different radii Optional push bending technique enables bending coils

Tube Configuration-plan NCSX

Tube Configuration-elevation NCSX

Typical Tube Drawing NCSX

Supply Header Configuration Following VG show assembly and configuration of Tubing, Headers, and Cryostat interface. Order is flexible, headers can go on first or last. Competing interfaces not shown - Magnetic Loops - Thermocouples - Heaters - Insulation NCSX

Tubes Installed on VV

NCSX Headers Installed

NCSX Tubes Installed on Port

NCSX Interface Flange Installed

Cryostat Interface-elevation NCSX Headers lie within Cryostat wall. -Gives access for diagnostics above flange -Requires only 4 bellows/port Insulation is backfill with Nanogel ® beads Notes 1. Feedthrough shown is projected view. Actual location lies within 6" region.

Cryostat Interface Flange Provisions NCSX 8 generic 2.75” CF flanges are provided at each interface Cost effective means to get gas seal between Cryostat/VV O-rings are adequate 3 flanges for thermocouple hookups (18 top/19 bottom pairs required) -10 pair positions on each flange -20 thermocouple positions total -Backups not connected) 4 flanges for magnetic loop hookups -19 pins each - 38 wire pairs (loops) total 1 flange for heater hookups - 4 pairs (includes backups)

Coolant Circuit Schematic NCSX Diagram is for full Field Period WBS 12 interface extends through electric break. Tubing alternates to two header systems, giving a degree of redundancy. - 2 ring headers on each side of port 12.

Reference Calculation Documents NCSX-CALC Vacuum Vessel Heating/Cooling Distribution System Thermo-hydraulic Analysis NCSX-CALC Vacuum Vessel Heat Balance Analysis Design Assumptions-Insulation - 75% efficiency - Microtherm or equivalent insulation - VV 2.54 cm - Port, 3.81 cm inside MC, 5 cm outside MC - Areas between MC assemblies filled - Port ends 2.54 cm System Design Parameters Coolant paths192 parallel Tube ID0.63 cm (.25”) Average length5.5 m CoolantGaseous Helium Operating Pressure20 atmos. abs NCSX Heating/Cooling Calculations

Bakeout at 350 C 17 kW required Idle Operation at 20 C 4.6 kW required Thermo-hydraulics at bakeout Pressure drop 0.12 atmos Entrance Velocity 22 m/s Temperature drop 17 K Flow rate 731 k/hr (285 cfm) Capable of 24 kW with He skid upgrade NCSX Results-Heating

Heat Removal (14.4 MJ shot) 16 kW Thermo-hydraulics Pressure drop 0.22 atmos. Entrance Velocity 24.5 m/s Average bulk temperature rise 4.9 K Flow rate 1660 kg/hr (305 cfm) Coolant entrance temperature20 C VV does not return to room temperature at this flow rate Bulk temperature rise is somewhat less than calculated - 1-D model does not take into account the partial VV coverage by the tubes Ratcheting discussed in later view graph, covered by DAC. NCSX Results - Cooling

NCSX-CALC Local Thermal Analysis - Freudenberg Analyzes cool down time, thermal ratcheting, clamp spacing, and thermal stresses in VV. Thermal Criteria – As set forth in SRD Cool down in 15 minutes for: 14.4 MJ pulse Even heat distribution VV returns to re-pulse temperature of C Results Cooling clamps on staggered 4” X 10” spacing pattern meets criteria. – Space is maximum, nominal spacing is much closer – Compacts at upper and lower regions VV stresses are acceptable NCSX Vacuum Vessel Cool down Analysis

NCSX VV Steady State Temperature As Function of Clamp Spacing Vertical Spacing Between Cooling Tube Clamps (inches) 4 Inch Horizontal Spacing 8 Inch Horizontal Spacing Steady state temperature (K) 14.4 MJ 15 minute cool down Temperature shown is max temp between clamps.

NCSX VV Temperature Response 14.4 MJ 15 minute cool down Temperature shown is max temp between clamps. Clamps on 4 X 10 grid (about average)

Ref. NCSX-CALC Local Thermal Analysis - Freudenberg NCSX Vacuum Vessel Stress 4 X 10 spacing – 38Ksi

Coolant Tube Build-to Specification NCSX Specification Covers the following: Applicable drawing and models. Drawings tabulate bending coordinates. Number of assemblies being fabricated (32 types, 6 of each) Standards, including stainless tubing, welding. QA Requirements for: welding cleaning weld inspection metrology leak checking permeability Contour tolerances are captured by drawings

FMECA NCSX Includes Heating/Cooling System Off-Normal Operation Loss of coolant Loss of heaters Abnormal port flange and/or VV temperature System integration of temperature monitoring and control Resistance Heaters Helium Coolant System Emergency shutdown Vacuum Vessel Temperature Control System

Issues NCSX Supports Lateral supports not yet analyzed Heating/Cooling R&D prototype of Coolant Tube may be required. Bidders are nervous about the complexity of the geometry.

Conclusion – VV Supports NCSX Support system strength is adequate for present and future operation. Analysis included the weight of port extensions, NB transition ducts, diagnostics, and upgrade PFCs. Support thermal isolation reduces the thermal load to the MC to an inconsequential level. The system permits thermal growth during temperature cycling. The system is adjustable and can align the VV in 6 axes. The system provides electrical isolation. Wherever possible, the system uses off-the-shelf commercial components.

Conclusion – Heating/Cooling System NCSX The system can provide adequate heat for idle and bakeout operation. The system can provide sufficient cooling to cool down the VV in the prescribed 15 minutes and stay within maximum steady state temperature requirement set forth in the SRD. The system is adequately insulated to reduce MC and Cryostat thermal loads to a manageable level. The stresses induced into the VV by thermal gradients are within safe levels. Provisions have been made to monitor temperatures, analyze them, and provide compensation in the event they are outside the design thresholds Interfaces through the Cryostat are provided which accommodates all of the cooling lines as well as local diagnostics, heater lines, and magnetic loops. Consequences of off-normal operation have been studied and documented in a FMECA. Commercial vendors were consulted to comment on the designs.