The superconducting chicago cyclotron magnet--An old magnet with a new pair of energy efficient coils

Significant electrical power can be saved by replacing existing water-cooled copper coils with superconducting ones. This paper describes a DOE-Fermilab energy conservation project in which a pair of superconducting tori 5.25 m in diameter have been constructed to replace the copper coils, built in 1949, of the 170-inch Chicago Cyclotron, now in use at Fermilab as an analysis magnet. The superconducting magnet, with a stored energy of 32.5 MJ, was fabricated in-house at Fermilab. Engineering concepts, design and optimization of the coil, support structure and cryogenic system are described. In particular, the major support, a composite column capable of a collapse load of 1.33 × 10⁶N and an expected heat leak of 120 mW will be described in detail. Practical problems encountered during the construction phase are discussed and test results presented.