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Polymer HIPing

Polymer HIPing

Polymer HIPing

(OP)
I am trying to find a liquid that can be pressurized to 5000psi and heated up to 700 degF.
I will be using this fluid in a pressure vessel with heater bands around it. What I am trying to do here is very similar to HIPing, where I want to substitute gas with a liquid. I will be HIPing Polymers/plastics. I am not sure how water behaves at these conditions. Also, I was looking into some polymer quenchants that I thought I could use. But, could not get much info.

Looking forward to hear your suggestions.

Thank you.  

RE: Polymer HIPing

Comeback with more information;

Is the liquid going to be in contact with the polymer?

Any organic is going to contribute to pressure is this a problem?

Could you possibly give the polymer family as you are getting into the range of violent decomposition with some polymer types.

All of our work on polymers at high pressure was done mechanically in vessels heated with molten salt or lead.  We did have some jacketed vessels heated with condensing Therminol or Dowtherm operating in you temperature range.

RE: Polymer HIPing

(OP)
unclesyd - first let me thank you for your response.. here is more info

Comeback with more information;

Q) Is the liquid going to be in contact with the polymer?
A) Yes the liquid will be in contact with the polymer.

Q) Any organic is going to contribute to pressure is this a problem?
A) I am not very sure what you are asking here.

Q) Could you possibly give the polymer family as you are getting into the range of violent decomposition with some polymer types.
A) This will be PTFE filled with PPS and other fillers..

All of our work on polymers at high pressure was done mechanically in vessels heated with molten salt or lead.  We did have some jacketed vessels heated with condensing Therminol or Dowtherm operating in you temperature range.

I will do some research on this..

Looking forward for your replies..

RE: Polymer HIPing

I don't think that you want the polymer in contact with the fluid.  You need a seal coating on it.

700F, that presents some problems.  There are some synthetic oils that might do the job.  PAO? Krytox?  A silicone based fluid?

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RE: Polymer HIPing

As your polymer will be in contact with the fluid my second question is mute.  Not being too clear, it was in respect to the partial pressure of the liquid in the chamber.

You are at the max temperature for temperature for the high temperature heating fluids, Therminol, Dowtherm, and  Syltherm.  

The highest temperature I’ve seen liquid ammonia at this pressure (5000 psig) is around 250°C.  I do know that some higher temperatures were used.  The question is whether it  will react with Teflon and PPS.  I don’t have any of the data from project/process.           

There is a possibility of using molten metals.  As I stated we have used lead for heating and as a carrier up to 2200°F.  Again the reaction with your polymers is the question.

I’m not sure about HIPing PPS as I seen extrusion pressures of 15,000 psig and 325°C.

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