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Thermal

Thermal

Thermal

(OP)
We are extruding 10 ft. long flexible PVC tubing.  When used to deliver solution during surgery,  the solution loses some of it temperature (gets colder).  Is there any material to coat the PVC tube to eliminate any heat temperature loss of the solution.

thanks

RE: Thermal

It would be easier with a bit more information. what temperature is the solution at when it enters the tube, and what is the allowable temperaute drop over that length. also what diameter is the tube and at what wall thickness.

also the room temperature that they are operating in and grade of PVC you are using for the application.

RE: Thermal

A coloration of opaque silver color will impart heat retention to the tube. The opposite is imparting a dull black color, which will encourage heat rejection from the tube.

RE: Thermal

plasgear,
I am interested to know how the colour of the tube effects the thermal properties and heat loss off the solution to the tube in reference to the solution and/or the ambient temperature. As far as i was aware the actual heat loss and how to reduce or improve this was dependant of the heat transfer coefficient of the materials, gases or liquids involved.
I understand that silver reflects light associated heat and black will absorb, but i am a little confused about its thermal thermal transfer. Would the silver masterbatch possibly draw more heat away from the solution as it is made up of metallic composites?

RE: Thermal

Coloration in silver is based on minimizing radiation heat transfer. It is one of the components of heat transfer from the tube. Conduction into metallic fillers should not be a worry because the amount of metallic filler would be minimal, a few percent.

RE: Thermal

Does your delivery line need to remain visible the entire 10 feet, or could, say, 9 feet of it be insulated with a pipe or tube wrap?  Also, how constant is the delivery volume?  Can you increase temperature at the output of the delivery unit according to your observed heat loss?  Just a few ideas, Good Luck!

RE: Thermal

Can you run a heated water jacket around a section to compensate for loss.

Can you co-extrude the pvc with a foamed layer.

Regards
pat

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