Superconducting magnet of magnetic resonance imaging system

The successfully commercial application of superconductivity is the superconducting magnet in the magnetic resonance imaging systems of $7 billion business global annually. Today over 35000 systems are used around the world and half millions medical imaging scanning are taken every day. As the most costly part of the system, superconducting magnet has many special requirements in order to perform the job, such as field of view(FOV), field strength, field uniformity, field persistence, stray field, shielding of external disturbance and boil-off rate of the Liquid Helium, etc. Some of these requirements are contradiction with each other, so a trade off is usually needed in the design and manufacturing. Alltech Medical Systems successfully developed 1.5 T superconducting magnet special for MRI system on Jan. 7, 2009 in Chengdu, China and more than over a hundred systems have been delivered to customs. Development of 3 T and 7 T (small bore) MRI systems are also in progress.