Conceptual Design of a 3T MRI Superconducting Magnet With Non-Thrust Face Integrated Former

Abstract

Recently, 3T MRI system has been one of the fastest growing segments of the MRI clinical diagnoses. In order to lower the 3T MRI cost and allow it to be more widely applied, especially in developing country like China, this paper presents a conceptual design of a 3T superconducting magnet with a non-thrust face integrated former for a whole body MRI system. The concept is an 8-coil active shielded magnet design with the minimized 82 cm standard warm bore size. The operating current is 480 A and the full field is 2.9T. The integrated former was designed to further minimize the coil internal diameter and reduce the superconducting wire length. Unlike traditional formers, there are no coil slots on the former for the coil supporting and positioning to reduce former manufacturing cost. The coils are wound and cast on a detachable mould tooling, and then bonded onto the outer surface of the integrated former. At 4.2 K, the coils remain bonded to the surface of the former; this prevents slight relative movement between the coil and the former in the coil energizing process. This coil-former structure can reduce the quench rate during the magnet ramping process to save liquid Helium and the build quality cost.