2000 degrees, 5000 psi tubing 1

[maggiemae]

I have a need for 1" tubing (and connections) for an application seeing 2000 deg F and 5000 psi in a subsea environment. I'm having difficulty finding it. Any suggestions?

 

[EdStainless]

What is the mean metal temperature? Are both the ID and OD at 2000F?
What is the minimum ID that you can accept?

= = = = = = = = = = = = = = = = = = = =
Plymouth Tube

 

[maggiemae]

The ID will see gas at 2000 deg F, the entire pipe will be subsea in ambient temperature of 40 deg. It will be 10 foot long and probably loose about 1000 deg by the far end of it.

 

[metengr]

From the question you asked it would seem to me that you are not directly involved with any of the design details. There is no information provided as to the purpose of this device. Are you looking to condense the hot gas at high pressure? What is the gas? Corrosion issues?

Sorry but this smells like a fundamental heat transfer/fluid flow research problem. Once the design details are known, material selection should be to ASME B&PV Code, Section VIII because of the elevated pressure concerns.

 

[maggiemae]

Thank you for your response. I am involved, though it is a new product and I am not to disclose its final purpose in a forum such as this. I am aware that there will be materials that can be made to work, my question is whether or not there are some "readily" available tube manufacturers that may have something to meet this, as making this new product cost effective is also a desire. I work with these pressures and higher all the time, what I have not had a lot of experience with is the elevated temperature.

 

[moltenmetal]

Tubing or pipe to handle 5000 psig (even external) at 2000 F simultaneously is a "purple squirrel". Good luck finding it.

Your mean metal temperature will be nowhere near 2000 F. You need to estimate that before you can begin this exercise.

 

[btrueblood]

Handling 2000F and 5000 psig sounds like a low-temperature combustion chamber. Rocket engines live near there. Rocket engines and similar combustion devices have active cooling systems to keep the wall material temperature to within design limits, typically the design life time is shortened due to the extreme thermal cycles and associated fatigue. You might look into ceramic coatings to line the i.d. as well, but good luck finding something easily implemented on the i.d. of a 1" tube.

I'm left wondering why you want to light a fire on the bottom of the ocean...

 

[maggiemae]

@btrueblood, you are astute. I'm looking at hasteloy, furnishes tubing for rocket and jet engines. Thank you.

 

[racookpe1978]

Are you ever going to run this "underwater, deep ocean rocket engine" above the surface for training, testing or or operations?

How are you actually intending to operate the thing? A deep-ocean (and water bottom change significantly!) operation would mean the outside of the tube is exposed to different water back-pressures, water temps (shallow, near-coastal down to your expected 4 degree bottom-of-the-trench worst/best case scenario.

Thus the diff pressure across the thing may have zero dp at one end (where water outside < gas pressure inside at the exhaust because the gas is leaving the chamber (but temp's are high inside the wall, very low outside the wall)) out to the other fixed end of the rocket chamber (where pressure inside >> pressure outside, but temp's are nearly the same.)

You're conditions and stresses are going to change down the tube. But, iff it is a one-time use item (like a thermite tube to weld underneath) who cares? You pay extra for the conservative wall needed to make sure it doesn't burn out the thermite liner, but even NASA couldn't tel how much their space shuttle booster shell was overdesigned. Turns out even that wassn't a exact, completely known value either.

 

[maggiemae]

@rocookpe....all good points and yes, the pressure variances are taken into account. I probably need to erase this thread. ;-|

 

[Metalguy]

>"You pay extra for the conservative wall needed to make sure it doesn't burn out the thermite liner, but even NASA couldn't tel how much their space shuttle booster shell was overdesigned. Turns out even that wassn't a exact, completely known value either."<

Same thing for the old Atlas rocket. One day something went wrong and it flew sideways w/o breaking up. USAF proceeded to make it lighter.

"You see, wire telegraph is like a very long cat. You pull his tail in New York and his head is meowing in Los Angeles. Do you understand this? Radio operates the same way: You send signals here, they receive them there. The only difference is there is no cat." A. Einstein