X-Mozilla-Keys:                                                                                 

Total nonsense. Silicone and teflon are the best high temp materials
you can get for these applications. The ratings on this stuff are
over 500 degrees. Teflon is one of the most inert of all plastics.

Some articulate disgruntled customer or even a competitor posing as
a customer can up load this crap to an Internet news group and
nobody checks. That's why I gave up on news groups a couple of years
ago.

Jeff Spitzer wrote:

I wouldn't be too sure.  Even though I was wrong on my guess about your
neoprene (I was thinking of Urethane which has decent oil resistance but
worse temp resistance) I'll take another stab at guessing on temp ratings.
IIRC, Teflon turns to butter at about 400F.  It also has a very CTE which
can lead to extrusion at high temps.  I'm not bashing the Hayes stuff and
make no bets about my numbers but do look into it yourself if you're
interested.

Jeff Spitzer

I got you on this one Jeff. Marks ME handbook page 6-39 the "softening
point" of 
Teflon is 750 F!!!!! "It is resistent to nearly all solvents
and chemicals". Amazing stuff!!

Silcone rubber is good up to 480 F for sort periods and 300 F for long
periods. Coating the silicone O ring with Teflon is ideal.
You get the low durometer and elongation (200%)  of the silicone with 
the temp capabilities of Teflon.

Paul Lamar
 
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