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Compressed
Asbestos Fiber (CAF) gaskets served industry's
needs for many years.
With the shift to nonasbestos gaskets, gasket
manufacturers have developed a myriad of replacement
products. Some of the initial materials developed
proved inferior to their asbestos based predecessors
in regard to temperature, chemical resistance,
creep resistance and sealing characteristics.
More recently Flexitallic has developed nonasbestos
gasket sheet products approaching, and in some
instances surpassing the capabilities of asbestos
sheet gaskets. Some of these products have been
fiber reinforced grades, manufactured by the traditional
calendering or sheeter process. Other product
ranges are fiber-free and some of these materials
have exceptionally good properties which exceed
the capabilities of CAF.
Flexitallic Thermiculite is a high temperature
gasket material based upon the mineral vermiculite.
The product is reinforced with a metal core and
is designed for use at temperatures which
exceed the capability of graphite based sheets.
The temperature capability of CAF is also exceeded
by Thermiculite.
The Flexitallic Sigma range of biaxially orientated
PTFE products has superb chemical resistance,
far exceeding that of CAF. These materials can
be used at temperatures from cryogenic to 260¡ÆC
(500¡ÆF). Being intrinsically clean they are especially
suitable for use in the food, pharmaceutical and
electronics industries.
Flexicarb is the name given to Flexitallic's range
of graphite based products. The range includes
graphite foil as well as graphite laminates which
contain reinforcing metal cores to overcome the
fragility of the non-reinforced foil. Graphite
products have excellent stress retention properties
and are resistant to most chemical media with
the exception of strong oxidizing agents. Reinforced
Flexicarb sheets are the standard sealing product
for many arduous applications in the petrochemical
and refining industries.
The Flexitallic SF and AF product ranges are rubber
bound, fiber reinforced sheets made by the traditional
calendering or sheeter process. A wide range of
fiber types are used, often in combination,
ranging from cellulose, rockwool and glass to
aramid and carbon.
Soft cut gasket sheets are typically used in Class
150 or Class 300 flanges; some of the metal reinforced
products can also be used in higher classes. The
temperture capability of the fiber/rubber
products is highly thickness dependent, with thin
gaskets having a wider service envelope than thicker
ones.
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