Title :
Measurement and analysis of axial end forces in a full-length prototype of LHC main dipole magnets
Author :
Artoos, K. ; Kurtyka, T. ; Savary, F. ; Valbuena, R. ; Vlogaert, J.
Author_Institution :
CERN, Geneva, Switzerland
fDate :
3/1/2000 12:00:00 AM
Abstract :
A full-length, twin aperture prototype (MBP2N1) dipole magnet for the LHC project was assembled at CERN with collared coils delivered by industry. The design of this prototype is close to that foreseen for the dipole series manufacture as far the coil geometry and that of the yoke components are concerned. The bolts that transfer the axial magnetic forces from the coil ends to the cold mass end plates were instrumented to verify the axial coil support. These axial forces were initially measured after partial assembly, during a standard and an accelerated cool down introduction to 1.9 K, and during magnet excitation up to 9.2 T. High force levels were observed, triggering a comparison with analytical models and measurements routinely made on 1-m single aperture dipole models. The prototype magnet was re-assembled with lower initial axial force settings and with additional instrumentation, to monitor these forces during the entire assembly process, and re-tested, to possibly correlate axial forces with training behaviour. This paper reports about the experimental observation and provides models towards their understanding.
Keywords :
accelerator magnets; colliding beam accelerators; proton accelerators; storage rings; superconducting magnets; 1.9 K; 9.2 T; LHC main dipole magnets; axial end forces; axial magnetic forces; cold mass end plates; collared coils; dipole series manufacture; full-length prototype; magnet excitation; yoke components; Apertures; Assembly; Coils; Force measurement; Geometry; Instruments; Large Hadron Collider; Magnetic analysis; Manufacturing industries; Prototypes;
Journal_Title :
Applied Superconductivity, IEEE Transactions on