Qualification of the LHC Corrector Magnet Production With the CERN-Built Measurement Benches
The LHC will incorporate about 7600 superconducting single aperture corrector magnets mounted in the main magnet cold masses. In order to follow up their production, we have designed and built 12 different benches for warm magnetic measurements based on rotating coils. Each bench was manufactured in two copies, one installed at the industry sites and the other kept at CERN for cross checks and monitoring of the measurement quality. These systems measure the main field, the field quality and the position and orientation of the field relative to the mechanical construction, all properties that are required for an effective use of the magnets. After calibration, the benches automatically refer the measured quantities to the mechanical interfaces used to align the correctors in the cold masses (pin holes or keys). In this paper we evaluate the global uncertainty achieved with the benches and compare the field measurements performed at room temperature in industry with measurements at 1.9 K performed at CERN on samples of each corrector type.
LHC Design Report Vol.1: The LHC Main Ring
The LHC Design Report is presented in three volumes: the first concerns the main ring, the second the infrastructure and general services and the third, the injector chain. The conceptual design was published in 1995 and this report provides a snapshot of the detailed design as it stands at the time of writing - early 2004
Experience with the Fabrication and Testing of the Sextupole Superconducting Corrector Magnets for the LHC
The LHC main dipoles will be equipped with sextupole corrector magnets with a field strength of 1700 x 2 (T,m) and a magnetic length of 110 mm to correct sextupole field errors. Within the LHC magnet programme CERN has developed in collaboration with CAT a cosine- type of design where much emphasis has been put on the cost reduction. The magnet features a two-layer racetrack coil, without end spacers, wound from a rectangular NbTi-wire. The two layers are wound simultaneously turning in opposite directions. The yoke is made of a scissor-type of lamination, which allows bringing the iron close to the coil for field enhancement. In this paper we review the manufacturing experiences with the first 12 prototypes bui lt at CERN and CAT. The results of the training at 4.2 K and 1.9 K are presented along with the magnetic field quality measured at room temperature and at 1.9 K.