High temperature flexible filament I need to cool some liquid (250&nbsp;°C) while it’s flowing through a tube which has to be able to bend and flex.
My idea is to make a flexible tube with a second tube spiraling around it through which coolant will flow.

I’d like to 3D print this tube if possible so I wonder if there is some printable filament that:


doesn’t melt at 250&nbsp;°C
is flexible enough that it can print some tube that can bend (bending radius of 30&nbsp;cm)
optimally also has good heat conductivity


Is there any 3D printer filament available that has these properties?
Ok, so to answer the primary question: What flexible filament will operate consistently at 250°C?
Man... this is a tough one. Some filaments, like PEEK and ULTEM 1010 can operate up in the 200c range.... but they're not flexible at all.
Silicon might be able to work, but you're still pushing boundaries.
Now.... I'm lucky to be in a 3D Printing company.... and we're testing a super-high-temp flexible material, very similar in temperatures to ULTEM. I'll definitely check back and let you know how it goes, but....
Honestly, that's so hot, readily available thermoplastics may not be an option unless you're in Aerospace with an unlimited budget..... which, based on the requirements, would make sense, lol!
I'd say the most readily available way to get this done would be 3D Printing a mold, in which to put your silicone, and bam -- you've got the part.