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Fluorocarbon Seal Information

Fluorocarbon Seal Information

Fluorocarbon Seal Information

Does anyone have literate on fluorocarbon seals?  I received a vendor analysis report that found fluorine and carbon in the system filters.  What fluids are compatible with fluorocarbon seals?  Is AS 1241 Synthetic Phosphate Ester compatible

I did a quick Google search for fluorocarbon seals, but only came up with two company's websites that sell seals.


RE: Fluorocarbon Seal Information

"Is AS 1241 Synthetic Phosphate Ester compatible"

Best seal material for that fluid is EPDM.

RE: Fluorocarbon Seal Information

Woops.  I meant to write 'are fluorocarbon seals compatible with phosphate ester'.  I'm aware that EPDM seals are the best option, but thank you, appreciate the feedback.  What I'm searching for is the compatibility with fluorocarbons.

hydtools, seems like you're indicating PTFE seals are made with fluorocarbons?  I'm quite ignorant on this subject, so forgive me if I'm making the wrong assumptions.  I'm thinking that only PTFE seals are made with fluorocarbons, or fluorocarbon based.  How about other seals?  Or are PTFE seals the only fluorocarbon based ones?

That brings me to another question.  We use PTFE lined flexible hoses.  I have not heard anything negative about that.

Thanks for the responses.

RE: Fluorocarbon Seal Information

Viton is a fluorocarbon.  
It is not compatible with phosphate ester.

EPDM is basically your only choice among elastomers.

PTFE is compatible, but it's not an elastomer.

In general, you shouldn't be finding significant amounts of fluorine or carbon in system filters in a phosphate ester system.  The finding suggests presence of a flurocarbon seal, somewhere, that shouldn't be there, and is telling you that it shouldn't be there by dissolving.


Mike Halloran
Pembroke Pines, FL, USA

RE: Fluorocarbon Seal Information

Thanks all!

RE: Fluorocarbon Seal Information

I should point out there are other possibilities.

Alcohol is the usual cleaning solvent for phosphate ester, but it's not inconceivable that some component may have been cleaned with a Freon (fluorocarbon) solvent, which might then appear in the system filters.

I personally would err on the side of caution and look for an unauthorized seal substitution.


Mike Halloran
Pembroke Pines, FL, USA

RE: Fluorocarbon Seal Information

Mike said it better than I did.  Common FKM elastomers are not suitable for phosphate esters.  This would include common Viton, though it's now known (according to Dupont) as Viton A, and most of its ripoffs clones.

There are some newer perfluoro elastomers (FFKM), trade names like Kalrez or or Parofluor that are listed as suitable, but you should probably test with your specific fluid as there isn't a lot of compatibility data for them yet.  Oh, and they cost a LOT of money.  

Parker lists their HiFluor compound as suitable for Skydrol, the phosphate ester hydraulic fluid I'm most familiar with (can still taste it...yech).  There are some newer versions of Viton (F?) that might be suitable also, if you like dealing with Dupont sales people.

RE: Fluorocarbon Seal Information


Fluorocarbon is an old company's name. This company manufactures, mainly, polymeric seals, so its range on plastics is wide.

Please, let us know the p/n or material code, so I can tell you what material can be.

As far as I don't know how to send you private messages, I can't give you further info (basically because I'm not certainly sure if this breaks the rules because it's commercial information).


RE: Fluorocarbon Seal Information

Looking at the  Skydrol and Pyrogard  It look like Green Tweed has Chimeras product to cover your sealing problem.
With Phosphate Esters I would contact the producer of the product for their recommendation.  I would also use the specific fluid when contacting a supplier of O-rings.


RE: Fluorocarbon Seal Information

I'd vote for the seals as the source also, but is the test labs report pointing to teflon, or was that an assumption based on flourine and carbon?
  If it is teflon, are there any NPT threads in the system that could have had teflon tape or paste applied over zealously? even a small blocking plug in some vendor component somewhere that had NPT threads and sealant?

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