[show abstract]
[hide abstract]
ABSTRACT: About 2500 superconducting sextupole corrector magnets (MCS) are
needed for the Large Hadron Collider (LHC) at CERN to compensate
persistent current sextupole fields of the main dipoles. The MCS is a
cold bore magnet with iron yoke. The coils are made from a NbTi
conductor, which is cooled to 1.9 K. In the original CERN design 6
individual sub-coils, made from a monolithic composite conductor, are
assembled and spliced together to form the sextupole. The coils are
individually wound around precision-machined central islands and
stabilized with matching saddle pieces at both ends. The Advanced Magnet
Lab, Inc. (AML) has produced an alternative design, which gives improved
performance and reliability at reduced manufacturing cost. In the AML
design, the magnet consists of three splice-free sub-coils, which are
placed with an automated winding process into pockets of prefabricated
G-11 support cylinders. Any assembly process of sub-coils with potential
misalignment is eliminated. The AML magnet uses a Kapton-wrapped
mini-cable, which allows helium penetration into the vicinity of the
conductor, increasing its cryogenic stability. Eliminating all internal
splices from the magnet significantly reduces heat loads and the risk of
magnet failure during operation. A tested prototype reached the critical
current limit of the conductor in the first quench
Particle Accelerator Conference, 1999. Proceedings of the 1999; 02/1999
