As part of the Jefferson Lab 12 GeV accelerator upgrade project, Hall B requires two conduction cooled superconducting magnets. One is a magnet system consisting of six superconducting trapezoidal racetrack-type coils assembled in a toroidal configuration and the second is an actively shielded solenoidal magnet system consisting of five coils. Both magnets are to be wound with Superconducting Super Collider-36 NbTi strand Rutherford cable soldered into a copper channel. This paper describes This paper describes a failure modes and effects analysis (FMEA) that was done on these magnets to identify their various failure modes, which were assessed in terms of their Risk Priority Numbers (RPN). Mitigating actions were identified that would reduce the RPNs to acceptable values.Index Terms-Conduction cooled, failure modes and effects analysis (FMEA), magnet quench protection, SSC-NbTi rutherford cable, superconducting magnet, torus.

The CLAS12 Torus is a toroidal superconducting magnet, part of the detector for the 12 GeV accelerator upgrade at Jefferson Lab. The coils were wound/fabricated by Fermilab, with JLab responsible for all other parts of the project scope, including design, integration, cryostating the individual coils, installation, cryogenics, I&C, etc. The paper provides an overview of the CLAS12 Torus magnet features, and serves as a status report of its installation in the experimental hall. Completion and commissioning of the magnet is expected in 2016.

No abstract

Thomas Jefferson National Accelerator Facility (JLab) refurbished the Large Aperture Solenoid Spectrometer (LASS) [1], 1.85 m bore solenoid, consisting of four superconducting coils to act as the principal analysis magnet for nuclear physics in the newly constructed, Hall D at JLab for the Glue Excitations Experiment (GlueX) [2]. The coils, built in 1971 at Stanford Linear Accelerator Center (SLAC) and used a second time for the Muon decays into Electron and GAmma ray (MEGA) Experiment [3] at Los Alamos, had electrical shorts and leaks to the insulating vacuum along with deteriorated superinsulation and instrumentation. Root cause diagnosis of the problems and the repair methods are described along with the measures used to qualify the vessels and piping within the Laboratory's Pressure Safety Program (mandated by 10CFR851). The extraordinary refrigerator operational methods used to utilize the obsolete cryogenic apparatus gathered for the off-line, single coil tests are described.