High Pressure Solenoid Valves

100 C ????

At 31 C Carbon Dioxide hits critical temperature where the liguid and gas portion have the same density, and the liquid phase disappears. At 100 C the pressure of CO2 is around 10,000 PSI, and your 1,000 PSI valve is history.

The critical point is a temperature and pressure and pressure point in any phase diagram, not a line or curve. However 73 atm calculates to 1,073 psi so the OP is asking for an irrational pressure level just below this pressure. I doubt that the pressure regulation accuracy will be sufficient to prevent a supercritical fluid from forming.

Phase diagram from http://www.teamonslaught.fsnet.co.uk/co2_info.htm

I suspect that this state uncertainty is why vendors may not specify a valve to operate at this level.

I do not understand though why a supercritical fluid originally at 31°C (304K) if heated to 100°C (373K) would now increase by an order of magnitude in pressure. This is not an order of magnitude in absolute temperature change and with the density no longer possible to change I only see a modest increase in pressure. However, I have never worked with supercritical fluids nor have I found an easy to find web search that explains what the pressure change of supercritical fluid will be when temperature changes. I doubt that the universal gas law applies now. Could you provide a link that can help clarify the pressure change.

I work with CO2 systems on a daily basis. When we are not controlling the CO2 using refrigeration, we store it in bottles that have 2 pounds of steel for every one pound of agent stored.

CO2 has a triple point as well, where all three stated can exist at the same time; a rather interesting fact.

I have researched and like you cannot find a chart for this. I know that my 2400 PSI reliefs will pop at 54 C. The highest temp/press in print I can find is 3500 PSI at 65 C. The 10,000 PSI at 100 C is a figure my cylinder manufacturer brandishes.

As I understand it, above the critical pressure, the pressure is difficult to model. Some use the Soave Redlich Kwong equations. I guess that is why charts are not available.

http://en.wikipedia.org/wiki/Supercritical_fluid

You can do a search on GlobalSpec©....

Thank you for that info and to all my other friends I am not into a refrigeration project so most of those numbers do not apply. I just need a source on solenoid valves as specified.. Thanks again.. great discussion but a bit off track re the valves.. Cheers

Did you try searching Global Spec?

Just did as Solar Eagle advised and have requested a quote..It is a great site and appreciate the leads and info.thanks again.

Well, as roy has identified redfred and solareagle collectively as a Good Answer, I will vote accordingly... I guess...

As I consider, GA to WJMfire as well. Sort of like corn on the cob: Good input, but not completely absorbed.