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A.Mortezania
19-02-2017, 08:46 PM
Dear Friends,

Do you have any experiences about working on cooling system for MRI machines in hospitals or do you have any source or any documents to help me understand how this system works ?

Thanks for your help in advance.

Sincerely yours.

botrous
26-02-2017, 11:25 PM
Dear,
MRI systems can be cooled by chilled water or city water depending on the manufacturer recommendation.
You need to have primary and secondary circuits if using chilled water.
Primary circuit will run the cold water between the chiller heat exchanger (refrigerant/liquid), the cooled liquid will be pumped to another heat exchanger (liquid/liquid) to cool the MRI cooling fluid.
Mainly (in most models) you need three 3 fluid outputs to the unit each with different flow , flow meters should be used to control the fluid flow in each part.

hope it is clear enough

regards

A.Mortezania
27-02-2017, 10:09 AM
Dear,
MRI systems can be cooled by chilled water or city water depending on the manufacturer recommendation.
You need to have primary and secondary circuits if using chilled water.
Primary circuit will run the cold water between the chiller heat exchanger (refrigerant/liquid), the cooled liquid will be pumped to another heat exchanger (liquid/liquid) to cool the MRI cooling fluid.
Mainly (in most models) you need three 3 fluid outputs to the unit each with different flow , flow meters should be used to control the fluid flow in each part.

hope it is clear enough

regards

Dear Botrous ,

Thanks for your information.

I have important question, I see that MRI cooling machine system as you told we have chilled water, OK.
But I see that they charge second circuit with helium refrigerant and helium decrease temperature of magnet of MRI machine near to 3 ~ 7 kelvin and it is very low temperature.

Do you know how helium do this ? and I want to know second circuit also has condenser and evaporator and compressor such as typical refrigeration system ? or it do as other cycle to cool magnet ?

You can see this video at below address :

Interesting chiller unit (extremely cool)
https://www.youtube.com/watch?v=BZL8kJ1lMDs

Sincerely yours.

botrous
09-03-2017, 03:55 PM
Hi in helium system the main chiller is used to cool the helium condenser , but I doubt that for an MRI you need such low tempreture, all the MRI I worked on work actually on normal cold water