High Temp O-rings
High Temp O-rings
(OP)
I am looking for an o-ring material that can withstand about 850-900F. I have found a perflouroelastomer material from Parker (FFKM) but it is only rated to 590F. This is for centering a .50" diameter "soldering tip" that is 12" long.
Am I running down an infinitely long and dark tunnel?
Am I running down an infinitely long and dark tunnel?
"Art without engineering is dreaming; Engineering without art is calculating."
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RE: High Temp O-rings
I think you will quickly find it to be a dead-end.
I'm not aware of any elastomer that's good to 900F. I think you need to be looking for a ceramic.
RE: High Temp O-rings
http://www.usseals.com/grafoil.htm
Ted
RE: High Temp O-rings
In my experience, 600 deg F is the very best you can do with an o-ring. Since this application is just a centering ring it is probably not required to seal anything. If this is the case, just make a ring out of ceramic. Macor can certainly take the temp and is machineable and readily available.
Timelord
RE: High Temp O-rings
Thanks all.
"Art without engineering is dreaming; Engineering without art is calculating."
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RE: High Temp O-rings
RE: High Temp O-rings
RE: High Temp O-rings
Here is one of many companies that make potting compounds for similar applications.
http://www.aremco.com/a2.html
Sauereisen is another supplier but the website is down.
If conductivity between parts isn't a problem.
In another fabrication we used a metal o-ring to center the two parts and then added the ceramic potting compound. If you use this approach make sure the ring is vented.
RE: High Temp O-rings
Rather, you need to be thinking in terms of graphoil or similar materials as used in the valve industry. I've used pure lead before, soft malable and readily accessable but cannot remember the melt point. Maybe a ceramic or specialty metal would work for you.
Good luck with your research.
Kenneth J Hueston, PEng
Principal
Sturni-Hueston Engineering Inc
Edmonton, Alberta Canada
RE: High Temp O-rings
so, a few more random thoughts:
Boron nitride, as a pressed powder, is much more machinable, and has better (lower) thermal conductivity than alumina, but not quite as good as silica. Foamed silica even better, but weaker.
A tightly fit ceramic tube, especially one cemented/potted around the metal, may fracture if you don't take care with CTE differences.
A good way to keep the ceramic from cracking due to vibration/handling is to pot it in place with some silicone RTV, if you can engineer a spot to put the RTV where the temp. stays below 500F or so.
There are solder glasses that can bond ceramics to metal.
www.cotronics.com is another supplier of ceramics in various guises.
RE: High Temp O-rings
Ouch!!!!! There's a jab.
-Dustin
Professional Engineer
Certified SolidWorks Professional
RE: High Temp O-rings
"Art without engineering is dreaming; Engineering without art is calculating."
Have you read FAQ731-376: Eng-Tips.com Forum Policies to make the best use of Eng-Tips Forums?
RE: High Temp O-rings
RE: High Temp O-rings
"Art without engineering is dreaming; Engineering without art is calculating."
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