Tip:
Viton® O-Rings
Genuine Viton® O-rings from DuPont Dow Elastomers are
Superior
Problem
Solving Products, Inc. is certified by Dupont Dow Elastomers
to sell Viton® o-rings. Be careful when buying Viton®
o-rings from an unknown distributor because the quality
may not be up to par. Whether you are buying from us or
someone else, we recommend you always make sure you are
dealing with a certified distributor.
Viton®
is a fluorocarbon rubber. The fluorocarbon rubbers were
first developed in the 1950s and have become very important
to the seal industry. Viton® has a low compression set,
is effective over a wide range of temperatures and is resistive
to many chemicals. The working temperature range for Viton®
is -15 degrees F to 400 degrees F, but it can sustain temperatures
up to 600 degrees F for a short period of time. In a static
application it will sometimes seal at temperatures down
to -65 degrees F but it should be carefully tested before
going into production.
Effect
of Temperature on Hardness in Viton® O-rings
The
hardness of elastomer vulcanizates decreases with increasing
temperature. The amount of the decrease depends upon the
nature of the elastomer, the degree of cure, and the amount
of plasticizer which is included in the compound.
Here
is a convenient rule of thumb: At any temperature between
250° and 500°F (121° and 260° C) vulcanizates
of Viton® are 15 to 16 durometer points softer than
they are at room temperature. Accordingly, if 75 durometer
A is required at 300°F (149° C) formulate for a
room temperature hardness of about 90 A.
Three major general use grades of Viton®
There
are three major general use grades of Viton® for o-rings
and seals: A, B and F. Please click here for extensive information
on Viton® grades.
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