3-D Mechanical Analysis of the ECR Source Magnet for FRIB

IEEE Trans. Appl. Supercond.

et al. 2019

The superconducting electron cyclotron resonance (ECR) source magnet for the facility for rare isotope beams at Michigan State University was designed and built by the Superconducting Magnet Group at Lawrence Berkeley National Laboratory (LBNL) in 2017. The 28 GHz NbTi ion source magnet features a sextupole-in-solenoids configuration which is comparable to the VENUS ECR magnet operated at LBNL. However, the mechanical design of this magnet utilizes a shell-based support structure which allows fine adjustments to the sextupole preload and reversibility of the magnet assembly process. The magnet has been assembled and tested to operational currents at LBNL. This paper describes the mechanical analyses performed to estimate the sextupole's and solenoids' preloads. We will report on the 3-D finite element analysis during room temperature assembly, cool-down, and magnet excitation, and then describe the magnet preload operations. Finally, we will describe the performance of the support structure during the quench training.

“…The FRIB ECR magnet structure ( Fig. 1), described in detail in [4] and [8], is comprised of the solenoid-mandrel subassembly and the sextupole coil pack subassembly.…”

Section: Magnet Parameters and Assemblymentioning

confidence: 99%

Mechanical Study of a Superconducting 28-GHz Ion Source Magnet for FRIB

Pan

Arbelaez

IEEE Trans. Appl. Supercond.

et al. 2019

“…The level of azimuthal stress in the sextupole during the bladder-key operations can be directly measured and monitored by installed strain gauges in the pads and compared against the calculated target stresses in the 3D model. As an example, 10 the calculated contact pressure of the sextupole coil against the pole at various stages of assembly is shown in Figure 3. Note that although the contact pressure is inhomogeneous along the mandrel length, it stays positive during all assembly steps and, in particular, after Cool Down (CD) and full excitation of Lorentz Forces (LF).…”

Section: Ghz Ecr Ion Sourcementioning

confidence: 99%

Status of ECR ion sources for the Facility for Rare Isotope Beams (FRIB) (invited)

Machicoane

Review of Scientific Instruments

Fogleman

et al. 2016

Ahead of the commissioning schedule, installation of the first Electron Cyclotron Resonance (ECR) ion source in the front end area of the Facility for Rare Isotope Beam (FRIB) is planned for the end of 2015. Operating at 14 GHz, this first ECR will be used for the commissioning and initial operation of the facility. In parallel, a superconducting magnet structure compatible with operation at 28 GHz for a new ECR ion source is in development at Lawrence Berkeley National Laboratory. The paper reviews the overall work in progress and development done with ECR ion sources for FRIB.

“…We present here a summary of the assembly steps and highlights on the mechanical analysis. Deeper analysis and model description can be found in [12].…”

Section: Magnet Assembly and Preloadmentioning

confidence: 99%

Design of a Superconducting 28 GHz Ion Source Magnet for FRIB Using a Shell-Based Support Structure

IEEE Trans. Appl. Supercond.

Rochepault

Hafalia

et al. 2015

Self Cite

The Superconducting Magnet Program at the Lawrence Berkeley National Laboratory (LBNL) is completing the design of a 28 GHz NbTi ion source magnet for the Facility for Rare Isotope Beams (FRIB). The design parameters are based on the parameters of the ECR ion source VENUS in operation at LBNL since 2002 featuring a sextupole-in-solenoids configuration. Whereas most of the magnet components (such as conductor, magnetic design, protection scheme) remain very similar to the VENUS magnet components, the support structure of the FRIB ion source uses a different concept. A shell-based support structure using bladders and keys is implemented in the design allowing fine tuning of the sextupole preload and reversibility of the magnet assembly process. As part of the design work, conductor insulation scheme, coil fabrication processes and assembly procedures are also explored to optimize performance. We present the main features of the design emphasizing the integrated design approach used at LBNL to achieve this result.