Recent Test Results of the High Field ${\rm Nb}_{3}{\rm Sn}$ Dipole Magnet HD2

-This paper reports on the assembly process and cool-down to cryogenic temperature of the support structure of FRESCA2, which is a dipole magnet for upgrading the actual CERN cable test facility FRESCA.The structure of the FRESCA2 magnet is designed to provide the adequate pre-stress, through the use of keys, bladders, and an Al alloy shrinking cylinder. In order to qualify the assembly and loading procedures, the structure was assembled with Al blocks (dummy coils) that replaced the brittle Nb 3 Sn coils, and then cooled-down to 77 K with liquid nitrogen. The evolution of the mechanical behaviour was monitored via strain gauges located on different components of the structure (shell, rods, yokes and dummy coils).We focus on the expected stresses within the structure after assembly, loading and cool-down. The expected stresses were determined from the 3D finite element model of the structure. A comparison of the 3D model stress predictions with the strain gauge data measurements is made. The coherence between the predicted stresses with the experimental gauge measurements will validate the FEM model of the structure. IndexTerms-dipole, EuCARD, magnet, Nb 3 Sn, superconducting accelerator magnet.

Section: Longitudinal Compression Systemmentioning

confidence: 99%

Assembly, Loading, and Cool-Down of the FRESCA2 Support Structure

Garcia

Giloux

Ziemiański

et al. 2014

“…4 (left), follows a similar concept as the one adopted for the magnet HD2 [10]. It is characterized by an external aluminum shell 65 mm thick, two iron yoke halves, and vertical and horizontal pads surrounding the coils.…”

Section: Magnet Design and Parametersmentioning

confidence: 99%

Development of the EuCARD $\hbox{Nb}_{3}\hbox{Sn}$ Dipole Magnet FRESCA2

Ferracin

Devaux

Durante

et al. 2013

The key objective of the Superconducting High Field Magnet work package of the European Project EuCARD, and specifically of the High Field Model task, is to design and fabricate the Nb3Sn dipole magnet FRESCA2. With an aperture of 100 mm and a target bore field of 13 T, the magnet is aimed at upgrading the FRESCA cable test facility at CERN. The design features four 1.5 m long double-layer coils wound with a 21 mm wide cable. The windings are contained in a support structure based on a 65 mm thick aluminum shell pre-tensioned with bladders. In order to qualify the assembly and loading procedure and to validate the finite element stress computations, the structure will be assembled around aluminum blocks, which replace the superconducting coils, and instrumented with strain gauges. In this paper, we report on the status of the assembly and we update on the progress on design and fabrication of tooling and coils. With an aperture of 100 mm and a target bore field of 13 T, the magnet is aimed at upgrading the FRESCA cable test facility at CERN. The design features four 1.5 m long double-layer coils wound with a 21 mm wide cable. The windings are contained in a support structure based on a 65 mm thick aluminum shell pre-tensioned with bladders. In order to qualify the assembly and loading procedure and to validate the finite element stress computations, the structure will be assembled around aluminum blocks, which replace the superconducting coils, and instrumented with strain gauges. In this paper, we report on the status of the assembly and we update on the progress on design and fabrication of tooling and coils.

“…On the one hand, superconducting magnets allowed increasing the bore magnetic field of one order of magnitude, from the 1.5-2 T limit of resistive magnets to the world record of nearly 14 T in a sizeable bore [1]. On the other hand, the progress since the first accelerator magnets in the 70's [2], [3] may look slow: 4 T in Tevatron at the beginning of the 80's, 5 T in Hera in the 90's, and 8 T still to reach for the Large Hadron Collider operation.…”

Section: Introductionmentioning

confidence: 99%

Limits to High Field Magnets for Particle Accelerators

Todesco

Ferracin

2012

What is the ultimate limit to high fields in superconducting magnets for particle accelerators? In this paper we review the present status of the technology, outlining the main limitations. We first analyse the needed margin for operating a magnet in an accelerator. We then review the relation between current densities, coil widths, and fields in the magnets build so far. The issue of stress and the dependence on the coil lay-out is then discussed: a careful optimization between current density and coil width can be needed to keep the forces and associated strain within acceptable limits.The main issues related to cable lay-out (strand diameter, filament size) are then discussed. We conclude by giving a hint on the requirements on a HTS conductor, and a summary of Nb-Ti and Nb 3 Sn. CERN-ATS-2012-052February 2012 Abstract 4AO-1 EDMS 1184259 1  Abstract -What is the ultimate limit to high fields in superconducting magnets for particle accelerators? In this paper we review the present status of the technology, outlining the main limitations. We first analyse the needed margin for operating a magnet in an accelerator. We then review the relation between current densities, coil widths, and fields in the magnets build so far. The issue of stress and the dependence on the coil lay-out is then discussed: a careful optimization between current density and coil width can be needed to keep the forces and associated strain within acceptable limits. The main issues related to cable lay-out (strand diameter, filament size) are then discussed. We conclude by giving a hint on the requirements on a HTS conductor, and a summary of Nb-Ti and Nb 3 Sn.