Ultra Shield Refrigerated Magnet Technology

Engineering expertise in superconducting magnet design

: 7T USR magnet

Modern magnets are available with shielding of the external magnetic field. This is achieved by use of a second superconducting coil which compensates the magnetic field outside the magnet. Bruker’s UltraShield technology drastically reduces the stray field to close to the magnet and thus strongly reduces the magnetic field to which the operator is exposed. All Bruker USR magnets include refrigeration technology for long helium hold time and minimum number of maintenance intervals.
more on USR magnet technology

The choice of magnet is central in defining an MR system. Its specification and characteristics are of major importance in determining the overall system performance. The optimal combination of magnet geometry and magnetic field strength is critically determined by the specific studies and applications of the end user as well as by siting considerations. Bruker BioSpin MRI manufactures a range of horizontal superconducting magnet systems with bore diameters ranging from 160 mm up to 400 mm and nominal magnetic field strengths ranging from 4.7 Tesla up to 11.7 Tesla.

Horizontal USR Magnets with Active Shielding and Refrigeration

Magnet	47/40	70/20	70/30	94/20	94/30	117/16
Magnetic Field (T)	4.7	7.0	7.0	9.4	9.4	11.7
Bore diameter (mm)	400	210	310	210	310	155
Free access for imaging (mm)	198	72	154	72	154	72
Flange to field center (mm)	745	675	745	745	1005	700
Max. drift rate (ppm/h)	0.05	0.05	0.05	0.05	0.05	0.05
5 Gauss radial/axial (m)	2.0/3.0	1.5/2.5	2.0/3.0	2.0/3.0	2.3/3.3	1.7/2.8
Homogeneous volume Peak-to-Peak (ppm)/dsv (mm)	+/- 5/180	+/- 5/120	+/- 5/180	+/- 5/120	+/- 5/180	+/- 2/60
Min. He refill intervall (days)	ZBO*	ZBO*	ZBO*	ZBO*	ZBO*	ZBO*
Min. ceiling height (cm)	285	285	285	285	285	285
Weight (kg)	4500	3000	5500	5500	11800	7000