Silicon have exceptional heat to Silicon passes excellent resistant
& comp resistance to temperature extremes. Flexibility below
- 1750 F. the maximum temperature at which silicones
are recommended for continuous service in dry air is 4500
Viton is the most significant single elastomer. Its working
temperature range is –200 F to +4000 F.
it has been known to Seal at –6500 F in some specific
Hypolone is useful to over a temperature range of –650
to 2500F. But its mechanical properties, compression
and permanent set characteristics are less than desired for
both dynamic and static sealing applications.
can be compounded for service at temperatures of –650
F to +3000 F. Most elastomers are either resistance
to deterioration from exposure to petroleum lubricants or oxygen.An
ASTM-specified oil resistance level based on an ASTM test.
is excellent resistance to Petroleum product and its ability
to be compounded for service over a temperature range of –650
to +2500F Nitrile is the most widely used elastomer
in the seal Industry today. An ASTM-specified oil-resistance
level based on an ASTM test (e.g. oil swell)
STYRENE BUTADINE RUBBER (SBR)
SBR Rubber is probably best known under its old destination
buna S or GRS (Government Rubber Styrene) which refers to the
rubber originally made during world war II in United States
Government – owned plants as a substitute for natural Rubber.
SBR and natural rubber account for approximately 90% of total
world rubber consumption. SBR is commonly recommended for automotive
brake fluid alcohol and water.
EPDM is an elastomer prepared from ethylene and propylene monomer
and at times with a small amount of a third monomer. It has
won broad acceptance in the sealing world because of its excellent
resistance to skydrol and other phosphate ester type hydraulic
fluids. EPDM has a temperature range of –650 to +3000
F for most applications.
Natural rubber is found in the juices of many plants including
the shrub quayule, Russian dandelion, galdenrod and dozens of
other shrubs vines and trees. The principal source is the tree
heavier prasiliensis which is native to Brazil, Petroleum oil
are the greatest enemy of natural rubber compounds commonly
recommended for Automotive break fluid.