400-Ton Tokamak Poloidal Field Coil Transport Manual
Critical engineering procedures for transporting massive ring-shaped superconducting magnets up to 30 meters in diameter: vacuum-pressure epoxy insulation preservation, multi-file SPMT synchronization, and sub-500 με flexural strain limits.
Superconducting Conductor & Epoxy Integrity
Tokamak Poloidal Field (PF) coils utilize Cable-in-Conduit Conductors (CICC) composed of thousands of brittle niobium-tin (Nb3Sn) or niobium-titanium (NbTi) superconducting strands encased in an incoloy or stainless steel jacket. The conductors are wound and impregnated under vacuum with radiation-hardened epoxy resin.
- • Micro-Crack Prevention: Tensile or shear strains exceeding 0.05% (500 micro-strain) cause micro-fissures in the resin, degrading electrical breakdown strength (dielectric withstand > 30kV).
- • Dry Helium Positive Pressure Purge: Continuous internal positive pressure (0.2 to 0.5 bar gauge) of 99.999% pure helium gas maintained across all cooling channels to detect micro-leaks.
- • Fiber Bragg Grating (FBG) Strain Sensors: Arrays of optical strain gauges embedded along the coil circumference monitored at 100 Hz by the Exspeedite in-cab telemetry hub.
Circular Grillage & Multi-File SPMT Array
Due to the extreme diameter (24m to 30m) and relatively low out-of-plane torsional stiffness of the annular coil, transport requires a specialized 30-meter radial steel grillage supported by a multi-file SPMT platform.
- • Radial Spider Truss Grillage: High-strength structural steel radial beams distribute the 400-ton ring load over 48 articulating elastomer support shoes with spherical bearings.
- • Multi-File 64-Axle SPMT Platform: Dual or quad-file SPMT modules coupled electronically via optical fiber CAN-bus, providing 360-degree all-wheel steering and crab modes.
- • Isostatic 3-Point Hydraulic Grouping: Suspension divided into 3 independent hydraulic compensation zones to prevent twisting moments during roadway camber transitions.
Dynamic Acceleration & Road Profiling
Road-induced vibrations and inertial loads during transport must be kept strictly below cryogenic superconductor tolerance envelopes.
- • Maximum Speed Limit: SPMT convoy velocity strictly governed to 4.0 km/h (2.5 mph) on highway sections and 1.5 km/h on gradient transitions.
- • Laser Profilometer Route Survey: Entire route pre-scanned with mobile LiDAR to mill asphalt bumps exceeding 10mm amplitude.
- • Hydraulic Active Dampening: SPMT hydraulic accumulators pressurized to attenuate resonant frequencies between 1.5 Hz and 8.0 Hz.
Tokamak Assembly Hall Ingress & Docking
Final docking at the Tokamak Building airlock requires cleanroom particulate controls and micro-metric positioning beneath the heavy crane gantry.
- • Clean Airlock Transition: De-dusting washdown and wheel-wash station prior to entry into ISO Class 8 assembly hall airlocks.
- • Laser Tracker Metrology Alignment: Leica AT960 laser trackers guide SPMT final resting coordinates within ±1.0mm tolerance.
- • Tandem Crane Pick Handover: 1,500-ton dual overhead crane synchronized pick from transport grillage to vertical sub-assembly jig.
Engage Fusion Magnet Transport Engineering
Submit your fusion facility coil specifications for custom grillage FEA and transport simulation.