Tri-clad is the name associated with any ThermaFoil product that
has the added protection of metal foil. This metal can be
a very thin foil for sealability or it can be thick for anti-extrusion.
All tri-clad seals are designed to enhance flexible graphite for
specific applications.
Tri-clad features
1) Oxidation prevention: capping flexible graphite with high temperature
metal protects the graphite from oxidation when temperatures exceed
850'f.
2) Vibration resistance: flexible graphite either as a gasket or
seal can be effected by high vibrations, such as aerospace, automotive,
or compressor applications. Cladding these seals eliminates vibration
fretting.
3) Seal removal: cladded seals can be removed with ease; this has
proven to be a big asset in aerospace, with their 100 hr. inspections.
4) Anti-extrusion: application where metal mating parts have gaps,
flexible graphite will extrude into these gaps. Metal caps are utilized
to prevent extrusion. Thickness of the metal depends on the pressure
and the gap.
Tri-clad parts differ slightly from normal graphite design due to their metal sealing surface. Standard sealability charts can
not be used. Refer to the following tri-clad styles and their appropriate sealing graph.
