Cooling Systems for magnetic resonance imagery (MRI) scanners

Thousands of patients depend on a body scanner to either detect a malignant growth or confirm that they are in the clear. A scanner is a vital piece of medical equipment which, without technology contributed from the air conditioning industry, would not function.

Process Cooling, the customised air conditioning arm of Eaton-Williams, first designed and supplied Oxford Magnet Technology (OMT) with a unit to cool a power supply module and magnet in 1995. This was a first for Eaton-Williams and required some innovative design and developmental work on the part of its engineers. Since then Eaton-Williams has extended its scope of supply to four coolers and ancillaries to three end users (via OMT).

OMT is one of the world leaders in the manufacture of super conducting magnets for Magnetic Resonance Imaging systems (body scanners), and has secured a Queen's Award for Export.

Process Cooling had to meet stringent criteria. Reliability and good design with a particular emphasis on size reduction were key considerations combined with the careful selection of materials and components.

With a high calibre in-house design team, Process Cooling is well used to combining technical expertise, research and design to provide economical, customised solutions. Most recent products have been designed using 'state of the art' design tools to improve design and shorten development time.

Scanners are complex, sophisticated pieces of equipment that have to be rigorously tested and manufactured to the highest standards. Two of the key components are the power supply and gradient coil. The temperatures within these components have to be precisely controlled to ensure sharp images.

Process Cooling designed the cooling system to operate remotely from the actual scanner. Once the scanner is activated the cooling unit switches on automatically and circulates water through a series of tubes within the gradient coil and a heat sink within the power supply. The whole system is a closed loop.