Experience on sheathing 10 km of cable-in-conduit conductor for the NHMFL 45-T hybrid

The superconducting outsert magnet for the 45-T Hybrid Magnet System being constructed for the National High Magnetic Field Laboratory (NHMFL) in Tallahassee, Florida will contain almost 6.5 km of cable-in-conduit conductor (CICC) in three different grades. The project is a collaborative effort with the Francis Bitter National Magnet Laboratory (FBNML) and industry. Counting dummy CICCs manufactured during the development phase of the project and excesses for contingency, well over 10 km (over 11 MA-m) will have been produced. To fabricate these conductors, a special production line was assembled by the industrial team of Intermagnetics General Corporation (IGC) and Gibson Tube. Components in the line were adapted from modern cable-handling and welded-tube-manufacturing machinery, with the addition of a computer data-acquisition system for process monitoring. The versatility of the IGC/Gibson line has been demonstrated by the production of three different grades of CICC in which the external dimensions, wall thicknesses, corner radii, and even conduit alloy were variables. This paper describes special features and capabilities of the manufacturing line as well as production rates and tolerances achieved in the final product