Gasket Material Options

Fluoropolymer (PTFE) Envelope

Fluoropolymer (PTFE) Envelope gaskets are soft, conformable gaskets which effect a seal at low boltload. They are designed to handle solvents and corrosives in the chemical field and are also widely used in food processing and other lines where contamination must be avoided.

Buna-N

Buna Nitrile is a Food Grade, 3A approved material that has good compression set and performs well with oils and animal fats.

Viton® / FKM

FKM (Fluoroelastomer/Viton®) is a USP Class VI, 3A tested and FDA compliant. FKM materials provide high acid and temperature resistance. Typical FKM Compounds do not have strong Base resistance and is especially vulnerable to Ketones.

EPDM

EPDM (Ethylene Propylene Diene Monomer) is a USP Class VI and 3A tested and FDA compliant elastomer with superior water resistance, good steam, high temperature resistance and better low temperature resistance than FKM materials. EPDM does not offer strong resistance to oil and animal fat. EPDM does not perform as well with acids as FKM.

Solid Fluoropolymer (PTFE)

Fluoropolymer (PTFE) - PTFE is a versatile high purity material. The only major drawback to PTFE is creep and cold flow.

Silicone - White Peroxide Cured

Peroxide Cured Silicone is 3A tested and FDA compliant. Silicone can be utilized for its natural high purity features with low extractables and extensive temperature range.

Silicone - Clear Platinum Cured

Platinum cured Silicone is USP Class VI, 3A tested and FDA compliant. Platinum Silicone compounds develop longer polymer chains than peroxide cured systems thus building a finished product with better mechanical properties and temperature range, both higher and lower temperatures. Platinum curing provides a non-blooming, high purity, peroxide free compound.

Gasket Material Properties
Property
VITON®
SILICON
EPDM
Temperature Range
-20 to 400° F
-29 to 204° C
-80 to 450° F
-62 to 232° C
-55 to 275° F
-48 to 135° C
Acid Resistance
Good
Good
Good - Excellent
Alkali Resistance
Poor - good
Poor - fair
Good - Excellent
Abrasion Resistance
Good
Good - Excellent
Good - Excellent
Compression Set
Good - excellent
Good - Excellent
Fair
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