Most MRI systems use a superconducting magnet (in short term being called: MRI Magnet), which consists of many coils or windings of wire through which a current of electricity is passed, creating a magnetic field of up to 3.0 tesla. Maintaining such a large magnetic field requires a good deal of energy, which is accomplished by superconductivity, or reducing the resistance in the wires to almost zero.
To do this, the wires are continually bathed in liquid helium at 452.4 degrees below zero Fahrenheit (269.1 below zero degrees Celsius).
In order to reach and maintain such a low degree, the Magnet casing of MRI system and its cooling system must be filled by Helium (H2) in liquid form. Each MRI machine in avarage needs 1700 litters of liquid Helium and the Helium must be refilled from time to time. Usually mass density of liquid Helium is 1.25 Kg/L, Which approximately means an operational MRI system needs over 2 metric tons of liquid helium with 99.999% purity.
To do this, the wires are continually bathed in liquid helium at 452.4 degrees below zero Fahrenheit (269.1 below zero degrees Celsius).
In order to reach and maintain such a low degree, the Magnet casing of MRI system and its cooling system must be filled by Helium (H2) in liquid form. Each MRI machine in avarage needs 1700 litters of liquid Helium and the Helium must be refilled from time to time. Usually mass density of liquid Helium is 1.25 Kg/L, Which approximately means an operational MRI system needs over 2 metric tons of liquid helium with 99.999% purity.
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