High Temp Insulation for test section 3

[George1979]

Hello everyone,

I'm in a desperate need for a polymer which I could use on my test section to electrically insulate parts of it. My problem is that we estimate that the temperature can reach up to 500C and that is why I have problems finding some.
I would like to ask as well if anyone could help me in finding a high temperature (up to 300 - 350C) thread sealing material - PTFE tape can go only up to ~250C so I need to find an alternative. Thanks to some of you from another forum I think that I should be looking for something like Grafoil tape - but any more information or alternatives would be greatly appreciated.
Thank you very much for your help in advance.

Kind Wishes,
George

ps
European or UK based companies would be ideal but I will be happy with any information.

 

[btrueblood]

George,

You mentioned electrical isolation, remember that graphite (main component of Grafoil) can be conductive.

 

[George1979]

Sorry maybe I wasn't too clear about my questions - there are two:
1)electrically insulating polymer polymer up to ~500C
2)thread sealant up to around 300C (doesn't have to electrically insulate) - so grafoil tape should be suitable but I can only find US suppliers - and maybe there are some alternatives for it?
Hope that clears things a little bit

Cheers,
George

 

[Demon3]

For point 1 I would say that there is no polymer that will survive because the carbon carbon bond is not stable to 500C. According to my one of my books ladder polymers could approach 500C but none are commercially available.

For the second point I would direct you to C.S. Hyde who sell just about every kind of polymer tape, sheet and foil there is. That includes high temperature polymers.

http://www.cshyde.com/

There is not any memory with less satisfaction than the memory of some temptation we resisted.
- James Branch Cabell

 

[unclesyd]

Grafoil or it's equivalent is fairly universal so check with gasket suppliers for the tape.

 

[btrueblood]

Demon3 has the correct answer. For electrical insulation above 350 C, you are in the realm of ceramics.

 

[George1979]

Thank you all for your input - that was much helpful - could you tell me please what are those polymers that could withstand 300-350C and where could I buy them?
Cheers,
George

 

[Demon3]

This is one of the best sites for such polymers.

http://www.solvayadvancedpolymers.com/

This site lists them all with properties too

http://www.boedeker.com/

Also, you can search for free by property at

http://www.matweb.com

You can get epoxy that retains mechanics including modulus to over 300C from

http://www.hybridplastics.com

(disclosure, I work there).

There is not any memory with less satisfaction than the memory of some temptation we resisted.
- James Branch Cabell

 

[unclesyd]

You might want to give Master Bond a call as they have a couple of resins that might work.

http://www.masterbond.com/sg/masterbond_htsg.pdf

 

[patprimmer]

PEEK or Victrex from Victrex. I think in Welwyn Garden City as they used to be ICI

http://www.victrex.com

Solvay recently aquired PEEK resins from Gharda. Gharda made some strong claims re development of new grades with exceptional properties even for PEEK. They also had what they called Super Sulphones. I can find their data if you have trouble getting it from Solvay. We lost the Gharda agency at that time as Solvay already had an established competent effective agent here.

Regards

eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.