The fabrication of cylindrical MRI magnetic and RF shields
Abstract
The authors have designed magnetic resonance shields for two magnetic resonance systems: 1) A 1.9 tesla, 60 cm bore superconducting magnet with a bruker biospec spectrometry system used for medical research, and 2) A 1.5 tesla, 100 cm bore superconducting magnet with a General Electric imaging system used for clinical diagnosis. The research system is enclosed by an iron cylindrical shield having a weight of 49,000 pounds. The diagnostic imaging system shield is a tapered thickness iron cylinder with conic ends having a weight of 100,000 pounds. The later shield was fabricated to control RF penetration and coupled to a coper RF end shield. Both shield designs were developed using finite element magnetic field computation methods using computed design facilities of the magnetic resonance system suppliers. The shields were constructed from cold rolled steel sections which were welded in place at the magnet site. The finished shields are supported by four saddle supports located in a concrete pit. The low carbon, specially annealed steel employed has particularly desirable properties of induced magnetism. The magnetic resonance system is supported on an aluminum support frame and floor such that the magnet center line is on the shield center line. Both shields restrictmore »
- Authors:
- Publication Date:
- Research Org.:
- Henry Ford Hospital, Detroit, MI
- OSTI Identifier:
- 7135980
- Report Number(s):
- CONF-850611-
Journal ID: CODEN: JNMEA
- Resource Type:
- Conference
- Journal Name:
- J. Nucl. Med.; (United States)
- Additional Journal Information:
- Journal Volume: 26:5; Conference: 32. annual meeting of the Society of Nuclear Medicine, Houston, TX, USA, 2 Jun 1985
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 47 OTHER INSTRUMENTATION; 62 RADIOLOGY AND NUCLEAR MEDICINE; MAGNETIC SHIELDING; DESIGN; FABRICATION; NMR IMAGING; SUPERCONDUCTING MAGNETS; COMPUTER CALCULATIONS; COST; MAGNETIC FIELDS; MAGNETIC INSULATION; RF SYSTEMS; STEELS; ALLOYS; DIAGNOSTIC TECHNIQUES; ELECTRICAL EQUIPMENT; ELECTROMAGNETS; EQUIPMENT; IRON ALLOYS; IRON BASE ALLOYS; MAGNETS; SHIELDING; SUPERCONDUCTING DEVICES; 440300* - Miscellaneous Instruments- (-1989); 550600 - Medicine
Citation Formats
Flynn, M J, Froelich, J W, Ewing, J R, Tomasik, M, Windham, J P, and Hearshen, D O. The fabrication of cylindrical MRI magnetic and RF shields. United States: N. p., 1985.
Web.
Flynn, M J, Froelich, J W, Ewing, J R, Tomasik, M, Windham, J P, & Hearshen, D O. The fabrication of cylindrical MRI magnetic and RF shields. United States.
Flynn, M J, Froelich, J W, Ewing, J R, Tomasik, M, Windham, J P, and Hearshen, D O. 1985.
"The fabrication of cylindrical MRI magnetic and RF shields". United States.
@article{osti_7135980,
title = {The fabrication of cylindrical MRI magnetic and RF shields},
author = {Flynn, M J and Froelich, J W and Ewing, J R and Tomasik, M and Windham, J P and Hearshen, D O},
abstractNote = {The authors have designed magnetic resonance shields for two magnetic resonance systems: 1) A 1.9 tesla, 60 cm bore superconducting magnet with a bruker biospec spectrometry system used for medical research, and 2) A 1.5 tesla, 100 cm bore superconducting magnet with a General Electric imaging system used for clinical diagnosis. The research system is enclosed by an iron cylindrical shield having a weight of 49,000 pounds. The diagnostic imaging system shield is a tapered thickness iron cylinder with conic ends having a weight of 100,000 pounds. The later shield was fabricated to control RF penetration and coupled to a coper RF end shield. Both shield designs were developed using finite element magnetic field computation methods using computed design facilities of the magnetic resonance system suppliers. The shields were constructed from cold rolled steel sections which were welded in place at the magnet site. The finished shields are supported by four saddle supports located in a concrete pit. The low carbon, specially annealed steel employed has particularly desirable properties of induced magnetism. The magnetic resonance system is supported on an aluminum support frame and floor such that the magnet center line is on the shield center line. Both shields restrict the 5 gauss field to within 4 meters from the magnet center line and produce minimal perturbations of the magnet homogeneity. The fabrication cost for each system is approximately $75,000 plus $1.55 per pound of installed iron.},
doi = {},
url = {https://www.osti.gov/biblio/7135980},
journal = {J. Nucl. Med.; (United States)},
number = ,
volume = 26:5,
place = {United States},
year = {Wed May 01 00:00:00 EDT 1985},
month = {Wed May 01 00:00:00 EDT 1985}
}